A bridge between computer hardware and software programs 1

I. Basic concepts of BIOS

When talking about bios, have you been concerned about it? In fact, whenever you press the power key on the chassis, it will really work for you. So what is bios? The book gave us a definition: "BIOS is short for Basic Input-Output System (Basic Input-Output System). It is responsible for initializing, setting, and testing various system hardware at startup, to ensure that the system works properly. If the hardware is abnormal, stop working immediately and report the error device information to the user. BiOS includes system power-on self-check (post) Program Module, the system starts the self-lifting program module, these program modules are mainly responsible for the main board and other computer hardware device communication function. "
Simply put, BIOS is a set of programs "Solidified" in computer hardware. It provides you with the lowest-level and most direct hardware control. BIOS is actually a bridge between computer hardware and software programs. It is actually a program or software. Our most intuitive understanding of it is the post (power on system test) function. When the computer is powered on, the BIOS will check all its internal devices for self-check, including testing of CPU, memory, read-only memory, system motherboard, CMOS memory, parallel and serial communication subsystem, floppy disk and hard disk subsystem, and keyboard. After the self-check test is completed, the system searches for the operating system in the specified drive and installs the operating system into the memory.

What is binary CMOS?

BIOS is stored in CMOS memory. CMOS is the first abbreviation of complementary metal-oxide semicondu. Chinese is complementary metal oxide semiconductor, which is a semiconductor technology, A pair of metal oxide semiconductor field effect transistor (MOs) can be integrated into one wafer. This technology is usually used to produce Ram and exchange application systems. The products produced by it consume extremely low power quickly, and have a high degree of tolerance for power supply interference. Specifically, this refers to a special RAM chip on the computer motherboard, which is usually 128 bytes or 256 bytes. The role of cmos ram is to save the hardware configurations of the system and set certain parameters for users.
Because the power consumption of cmos ram is extremely low, the backup battery on the cmos ram * motherboard can be powered off after the system power is off. Therefore, the user setting parameters stored in the CMOS will not be lost. Cmos ram is only a storage chip and only supports data storage. Special Programs are required for parameter settings in CMOS. The CMOS setup program of early computers is stored on a floppy disk. it is inconvenient to use that floppy disk for each setup. At present, most manufacturers have solidified the CMOS setup program-bios into the flash EPROM chip. The flash EPROM chip capacity is generally 1 MB and 2 MB, now there are a lot of 815e boards up to 4 MB (4 MB Haha, you can put a picture of the mm, the camera will show a picture of the MM think cool, however, the boot logo is only 256 colors, but it is still a little uncomfortable ). To facilitate viewing the BIOS capacity, we can identify the models on the BIOS chip: like 27c010, 27C512 and so on with "27" headers are EPROM (486 and less than 486 of the computer using the chip), while 28c010, 29c010, 29c020, 29c040, etc., are EEPROM, 29c010 is 128 K * 8, that is, 1 M bit Parallel EPROM, 29c010 is 128 K * 8 (1 M bit), 29c020 is 256 K * 8 (2 M bit) 29c040 is a 512 K * 8 (4 M bit) Flash ROM (586 and PII, piII BIOS chip ). Serial EEPROM is rare on the computer motherboard, and most of the manufacturers that provide these chips are MX, WINBOND, Atmel and other manufacturers.

Three BIOS settings and their impact

Currently, the most widely used motherboard BIOS mainly comes from American megatrends's AMI bios, award's Award bios, and Phoenix's Phoenix BIOS, early 486 machines also had some, such as eurosoft's euro bios and microid Research's Mr BIOS. Currently, the most common use of the motherboard is the Award bios. In addition, there are a few windows Windows bios that use AMI on the main board. After the system is started, winbios automatically recognizes the mouse. When a mouse is inserted on the computer, you can directly use the mouse to set the BIOS. The three BIOS entry methods are also slightly different. Award bios and ami bios press the <Delete> key while starting the system, and Phoenix BIOS press the <F2> key, there are also some BIOS methods vary depending on the vendor. Generally, press <anykey> appears in the lower left corner of the screen after power-on (specific analysis of the motherboard) to enter setup.

Here is a rough introduction to BIOS settings:

(1). BIOS features setup
1. virus warning/anti-virus protection (virus warning/anti-virus protection)

Option: enabled, disabled, chipaway

When this option is set to enable, if any software is trying to rewrite the boot sector or file allocation table, the BIOS will automatically display a warning window, the software is modifying the boot sector or file allocation table. This option can be enabled if you want to disable any software rewrite boot sector or file allocation table through BIOS. Of course, it is worth noting that this function can only protect the boot area and file allocation table from being rewritten, but cannot ensure that the content on the hard disk is not infected with viruses or changed by other disk tools.
It is worth noting that when this option is set to enable, some disk tools or the system reports an error when Windows 95/98 is installed, and the installation fails.
Some motherboard manufacturers have built-in viruses in BIOS. Code So that the system will not be attacked by some Boot viruses, but the current virus update speed is far faster than the motherboard virus code update speed, enabling this option does not effectively prevent attacks against the current popular viruses, but at least it can prevent attacks against some viruses. We recommend that you enable this option, but it does not consume much resources.
2. CPU Level 1 cache (CPU Level 1 cache)

Option: Enable and disable

This BIOS option is used to enable or disable the CPU level-1 cache. Of course, we strongly recommend that you enable this option for system performance. However, this function is mainly set for some super-frequency fans. For example, when the first-level cache of the CPU is enabled, a competition between 450 A and MHz can exceed the upper limit, however, if the first-level cache is disabled, it may be more stable than the first-level cache. Do not disable this option if you do not overspeed the CPU because the system does not know how it will slow down when the first-level cache of the CPU is disabled.
3. CPU Level 2 cache (CPU Level 2 cache)

Option: Enable and disable

This option is used to enable or disable the second-level cache of the CPU. The main function is to ensure high frequency stability. The Intel CPU-based secondary cache is integrated into the CPU, while the socket7 motherboard's secondary cache is integrated into the motherboard. After the second-level cache is disabled, the CPU overclocking performance will be better, but the overall performance will sacrifice a lot. This is the main reason why the lack of second-level cache competition 266 is better than the same-frequency p266, but the overall performance is always not good.
4. CPU L2 cache ECC checking (CPU Level 2 Cache ECC verification)

Option: Enable and disable

This option enables or disables the secondary cache error correction function of the motherboard. (Some boards have this function, and some do not ). We recommend that you enable this option, because after enabling this feature, the BIOS can automatically detect and correct the data stored in the second-level cache, making the system more stable. Especially for some systems that often encounter errors after high frequency, the function of opening an error significantly reduces the chance of errors. However, the error correction is performed at the cost of system performance, and some CPUs with higher performance will become worse if the function is turned on. It seems that stability and speed cannot be both done. It depends on how you think about it.
5. Quick power on self test (quick self-check)

With this option enabled, the system will ignore some BIOS self-recommended processes to make the startup faster. However, after you change the hardware configuration or report an error in system self-check, you can disable this option so that the BIOS can perform a more comprehensive detection. Of course, you can enable this option again after self-check.
6. boot sequence (boot sequence)

Option:
A, C, SCSI/EXT
C, A, SCSI/EXT
C, D-ROM,
CD-ROM, C,
D, A, SCSI/EXT (requires at least two IDE hard disks)
E, A, SCSI/EXT (at least three IDE Hard Disks are required)
F, A, SCSI (requires at least four IDE hard disks)
SCSI/EXT, a, c
SCSI/EXT, C,
A, SCSI/EXT, c
Ls/zip, c

This option allows you to set the BIOS to find the operating system from that disk. Generally, the operating system is installed on the drive C and should be started from the drive C. If a SCSI hard disk is used, select the sequence from SCSI startup first. If the hard disk fails to be started, start from disk A because of the settings. Use the boot disk to boot the system, repair the system, or install the system. If disk A is set to start from disk A at other times, if disk A does not have a boot disk, Windows will prompt you to start the disk first. Therefore, this option can reduce the unnecessary steps for BIOS searching for the operating system and reduce the startup time.
For some special motherboard (such as the be6 and bp6 of the upgrade), because the Board carries a special ide controller, the SCSI option is missing in the startup sequence, and an additional ext option is provided. This option allows you to start from the third or fourth ide device or from the SCSI device. The specific settings are described in boot sequence ext means.
7. boot sequence ext means (startup sequence ext Mode)

Option: IDE, SCSI

This function can be enabled only when ext is selected in the preceding startup sequence. If you want to start from the third or fourth ide device, you must first select Ext, C, A from the boot sequence startup sequence, and then select IDE in the boot sequence ext mean. If you need to start the SCSI device first, repeat the first step and select SCSI in the boot sequence ext means item.
8. Swap Floppy Drive)

Option: Enable and disable

This option enables you to adjust the logical drive letter of a soft drive. When you have two soft drives and need to change their logical drive positions, you do not need to remove them from the new drive, set the option to enable. The original A: Drive will be automatically mapped to B: Drive, while B: Drive will become :. This function is mainly prepared for two different formats of the software drive. Because the BIOS can only be started from a: of the two soft drives, you only need to use this option to enable the BIOS to start from any soft drive (of course, you need to enable both of them !)
9. boot up floppy seek (search for soft drive at startup)

Option: Enable and disable

This option controls whether the BIOS automatically searches for a soft drive when it is started. If it is set to enable and the BIOS cannot find the soft drive, an error message is automatically displayed, indicating that the soft drive cannot be found, the BIOS automatically monitors whether the floppy disk is 40-track or 80-track. It is best to set disable for this option.
10. boot up numlock status (keypad status at startup)

Option: On, off

This function controls the status of the keypad at startup. If it is set to on, the keypad will be in the numeric state (used to enter a number), but if it is set to off, the keypad will be in the cursor control state (used to control the direction of the cursor ).
11. Ide HDD block mode (IDE Hard Disk Block Mode)

Option: enabled, Disabled

Its function is to enable the hard disk to transmit files from multiple blocks, mainly to accelerate the transmission speed of the hard disk. When you set it to enable, the BIOS automatically checks whether your hard disk supports this function and configures various parameters. Almost all hard disks now support this feature, so you have no reason to disable it.
But all the winnt4.0 users should pay attention to it. Windows NT does not support this function. If this option is enabled, data may be lost. Therefore, Microsoft recommends that users of winnt4.0 disable this option.
Needless to say, disabling this option will reduce the transmission speed of the hard disk. Therefore, you must disable this option when using winnt. In other cases, it is best to set this option to enable to improve the system performance.
12. typematic rate setting (continuous key hit rate setting)

Option: enabled, Disabled

When you need to continuously press the same key, this option allows you to control the speed of the key. If it is set to enable, You can manually adjust the speed of the key strike and the pause time. If it is set to disable, the BIOS uses the default settings.
13. typematic rate (chars/sec) [continuous key hit rate (character/second)]

Options: 6, 8, 10, 12, 15, 20, 24, 30

When you press the same key repeatedly, this option allows you to control the repetition rate of each character, in every character/second, but you must first set it to enabled in typematic rate setting.
14. typematic rate delay (MSEC) [consecutive key-hitting Delay Time (microseconds)]

Options: 250,500,750,100 0

When you repeatedly press the same key, this option controls the pause time of each character, in milliseconds, that is, the number of milliseconds before each character appears. Of course, you need to set it to enabled in typematic rate setting.
15. Security Option)

Option: system, setup

After the system option is enabled, a password input window appears each time you start the system. Only the correct password can be entered to start the computer.
As for the setup option, you need to enter the password when entering the BIOS, this function is mainly used when you are a system administrator to only allow your users to use the computer and prohibit them from modifying the BIOS settings.
16. Assign IRQ for VGA (specify IRQ for the video card)

Option: enabled, Disabled

You can assign an IRQ to the VGA video card. Nowadays, more and more video cards need to allocate an IRQ to work. When you use these types of video cards and disable this option, the quality of the display may decrease or be unstable. Therefore, you 'd better check the video card before setting this option. You 'd better enable this option. If the video card is not required, you can save the next IRQ.
17. OS select for DRAM> 64 MB (the operating system selects memory> 64 MB)

Option: OS/2, non-OS/2

When the system memory is larger than 64 MB, OS/2 manages the memory differently from other operating systems. Therefore, the OS/2 mode is selected only when the IBM operating system OS/2 is used, and all other operating systems are selected as non-OS/2.
18. hdd s. m.a. R. T. capability (Hard Disk S. M. A. R. T. Function)

Option: enabled, Disabled

This function is used to enable or disable the S. M. A. R. T. Function of the hard disk. Currently, hard drives on the market almost all support s.m.a.t.t (self-Monitoring Analysis and Reporting) technology. With this feature enabled, the system can monitor possible hard disk errors at any time, so that you can have enough time to back up your important data before the hard disk fails, this saves your important data. Therefore, it is strongly recommended to enable the S. M. A. R. T. Function of the hard disk. Even if you disable this function, it will not bring a slight performance improvement to the system.
19. Delay ide initial (Sec) (delay ide initial time)

Options: 0, 1, 2, 3,..., 15

This option is used to delay the initialization time of some ide devices. These older ide devices can be rotated only after initialization. Otherwise, these ide devices cannot be detected. If you do not have such an older ide device, you 'd better set the latency to 0 to speed up startup.
20. processor number feature (processor serial number function)

Option: enabled, Disabled

This is an option about the serial number of the 3 series. As for this feature, I don't want to talk much about it. The major media had a large report some time ago. I think all readers are very disgusted with Intel's unauthorized work, so we can disable it in BIOS.
21. Video BIOS shadowing (ing video BIOS)

Option: enabled, Disabled

When set to enable, the video BIOS is automatically mapped to the system memory. In this way, the system can call the video BIOS faster through the 64-bit memory bus to improve performance. However, the current operating system has completely jumped through the video BIOS step and directly called the hardware resources of the video card. Since video BIOS is not directly called, it is useless to map it To the memory. It will only waste your memory resources.
Of course, it is not completely useless to enable IOS. Because dos games cannot call the hardware resources of the video card, they must use the video bios. Therefore, only when you are a DOS game player can you improve the display performance, you can set this option to enable.
22. Shadowing address ranges (XXXXX-XXXXX shadow) (ing memory address XXXXX-XXXXX)

Option: enabled, Disabled

With this option, you can manually select ing from memory address XXXXX-XXXXX for the remaining adapter. If you have not added a new adapter within this memory address, set this option to disable. At the same time, just like ing the video bios, if you are using Win95/98, you do not need to enable this option after installing the correct driver for the new adapter.

(2). chipset features setup
1. SDRAM Ras-to-cas delay (SDRAM RAS-CAS delay)

Option: 2, 3

This option allows you to set the delay time for the RAS-CAS. When set to 2, the latency of the SDRAM memory can be reduced to improve the speed of memory read/write. If the system is unstable after it is set to 2, it can be restored to the original default value of 3.
2. sdram cas latency time (sdram cas wait time)

Option: 2, 3

This option is used to control the wait time after the SDRAM receives a READ command. The less wait time, the faster the transmission speed. However, some SDRAM become unstable after the waiting time is set to 2. Therefore, it is best to set this option to 2 when the memory permits. Of course, if the system becomes unstable, it should be restored to the default value of 3.
3. SDRAM leadoff command (SDRAM start command)

Options: 3, 4

This option allows you to manually adjust the time when the system calls data stored in the memory. Select 3 to Improve the Performance. If it is unstable, it can be restored to 4.
4. DRAM data integrity mode (memory data integration mode)

Option: ECC, non-ECC

This BIOS option is used to set the memory type. If your machine is equipped with memory with ECC function (usually this memory is used on the server), after setting this option to enable, the system will automatically detect and correct the error of odd digits in the memory. However, for errors of even digits, the system can only detect but cannot correct the error. In this way, although the speed is reduced, the system runs more stably. Therefore, it is recommended that all readers who use ECC memory open this option, but for other DIY users who use general memory, select non-ECC. Otherwise, some minor problems may occur.
5. system BIOS cacheable (system BIOS buffer)

Option: enabled, Disabled

This function is used to enable or disable the system BIOS rom from using the area of the F0000h-FFFFFh in the secondary cache as a buffer. With this option, the system will greatly improve the speed of calling the system bios. However, the operating system we use seldom calls the system BIOS directly, even if you increase the speed of calling the system bios, it will not increase the overall speed. Therefore, this not only improves the speed, but also sacrifices the precious second-level cache. On the other hand, if a program is written to this memory address, the system will crash. To ensure system performance and stability, we recommend that you
Disable this option.
6. Video BIOS cacheable (Video BIOS buffer)

Option: enabled, Disabled

This function is used to enable or disable the video BIOS Rom to use the area of the C0000h-C7FFFh in the secondary cache as a buffer, the same as the system BIOS buffer, this function also sacrifices the valuable level-2 cache to store the video BIOS. At the same time, if a program is written to this memory address, the system will crash. Therefore, we recommend that you disable this option.
7. Video RAM cacheable)

Option: enabled, Disabled

This function is used to enable or disable the system BIOS rom from using the area of the A0000h-AFFFFh in the secondary cache as a buffer. This will greatly increase the speed of video memory and system data exchange, but it cannot increase the overall speed of the system. Most video cards have a bandwidth of at least 1.6 Gb/s (100 bit x 0.8 MHz), while the bandwidth of SDRAM is only about 100 Gb/s (64bit x MHz. Because the second-level cache bandwidth of the P2-500 is 2.0 Gb/s, the main bottleneck of the system exists in the second-level cache and primary memory, rather than the second-level cache and memory. It is more reasonable to use the second-level cache to cache the memory. On the other hand, if a program writes the memory address that is used as the buffer for the video card, it will also cause the system to crash.
8.8-bit I/O recovery time (8-bit I/O reply time)

Options: Na, 8, 1, 2, 3, 4, 5, 6, 7

Because the PCI bus is faster than the ISA bus, some older ISA cards cannot work well in the PCI bus. To solve this problem, the BIOS option allows you to manually adjust the cycle of the ISA Device. Setting it to Na will undoubtedly bring better performance to your old ISA card. Of course, this option is useless if you do not have an ISA card.
9. memory hole at 15 M-16 m (memory segment addressing at 15 M-16 m)

Option: enabled, Disabled

Some special ISA cards need to work in this memory address. When this option is enabled, a memory address is reserved for the ISA card, and the system can only use 16 MB of memory. So, unless your ISA card needs to enable this option to work, you 'd better disable this option.
10. AGP aperture size (MB) (AGP channel size)

Options: 4, 8, 16, 32, 64,128,256

This option allows you to specify the maximum amount of memory that can be used by the system Master Card, and manually specify the maximum size that can be used by the system Master Card. However, this is not closely related to the improvement of system performance. Currently, games require a large amount of memory to store textures. Therefore, you can set the maximum value here.
11. Auto Detect dimm/pci clk (automatic detection of dimm/PCI devices)

Option: enabled, Disabled

This option is set to reduce electromagnetic interference. After it is set to enable, the BIOS can monitor the statuses of The AGP, pciand SDRAM slots. If no card is available in these slots, the BIOS will disable the clock signal of these slots, which reduces the electromagnetic interference in the chassis and makes the system more stable, but this will sacrifice some performance. Therefore, if your computer does not have any electromagnetic interference problems, we recommend that you disable this option to improve system performance!
12. Flash BIOS protection (BiOS anti-write protection)

Option: enabled, Disabled

This function is set to prevent the BIOS from being refreshed by another user using a fl tool. When set to enable, you can enable anti-write protection. Of course, if you want to refresh the bios, you must set this option to disable. Otherwise, it is not successful to refresh the BIOS. BiOS protection is a very useful feature. Do you still remember the CIH virus raging some time ago? For most DIY, the data on the hard disk is not very important, but the BIOS is flushed... As a result, various anti-virus software companies are making a huge profit. Now, you only need to enable this function to prevent viruses from flushing the BIOS at will.
13. hardware reset protect (hard start protection)

Option: enabled, Disabled

This function is mainly set for all-day file servers and routers. When it is set to enable, the reset key on the chassis panel will become ineffective, in this way, you will not restart the server because you accidentally touch the reset key. If it is set to disable, the reset key will return to normal. Therefore, it is most appropriate for most users to set disalbe.

(3). Integrated peripherals
1. onboard IDE-1 controller (onboard IDE-1 Controller)

Option: enabled, Disabled

This feature allows you to activate or disable the first ide controller on the motherboard. In general, the onboard ide controller is active. If it is set to disable, all ide devices on this interface cannot work. If no ide device is used, you can set disable to save one IRQ for other devices.
2. onboard IDE-2 controller (onboard IDE-2 Controller)

Option: enabled, Disabled

Onboard the second ide controller. This feature allows you to activate or disable the second ide controller on the motherboard, just like the previous one.
3. Master/Slave drive Pio mode (Master/Slave drive Pio mode)

Options: 0, 1, 2, 3, 4, auto

This option is usually associated with the onboard IDE-1 controller or the onboard IDE-2 controller option. If you disable any onboard ide controller in the preceding options, the 'primary/slave drive Pio mode' option corresponding to this ide controller will become grayed out. Therefore, Pio (programmed input/output) mode of the IDE device can be set through this option only when the previous onboard IDE-1Controller or onboard IDE-2 controller is set to enables. In general, it should be set to auto. However, if you are an overclocking enthusiast, You Can overclock the IDE device in this option. To ensure the stability of the hard disk, the hard disk manufacturer lowered the transmission mode of the hard disk before leaving the factory. Now we can use this to improve the transmission mode of the hard disk and thus increase the transmission rate of the hard disk. How are you not going to overclock your old hard disk? Here, we only need to set the hard disk mode to a higher value to get a higher transmission rate. Like a high-frequency CPU, a hard disk with a high-frequency bandwidth may lose data, but it is the most important thing for an old hard disk to play its role. However, it should be noted that the old hard disk is referred to here. If you are using a new hard disk that supports udma, be sure not to 'fdown' your hard disk.

The following figure shows the transmission rate of the IDE device In PIO mode:

Maximum Pio data transmission rate (MB/s)
Pio Mode 0 3.3
Pio Mode 1 5.2
Pio Mode 2 8.3
Pio Mode 3 11.1
Pio Mode 4 16.6
4. Master/Slave drive ultra DMA (Master/Slave drive ultra DMA mode)

Option: auto, Disabled

This option is also associated with the onboard IDE-1 controller or the onboard IDE-2 controller option. If you disable any on-board ide controller in the preceding options, the 'master/Slave ultra DMA mode' option corresponding to this ide controller will become grayed out. Here we can activate or disable the ultradma transmission mode (if supported by the hard disk ). In general, you should set it to auto so that the BIOS can automatically check whether the hard disk supports ultradma. However, it is worth noting that the real implementation of dma33 or dma66 requires the support of the operating system. This option is only enabled in the BIOS. After entering Win95/98, right-click "my computer" and select "property". Then, select "DMA" in the hard disk attribute project, for some via boards, the DMA options in hard drive properties are gray, so you need to install the via four-in-One patch before you can select the DMA project.

The following lists the DMA mode transfer rates:

Maximum DMA transmission rate (MB/s)
DMA mode 0 4.16
DMA mode 1 13.3
DMA mode 2 16.6
Hyper-ADMA 33 33.3
Ultradma 66 66.7
5. Ultra DMA-66 ide controller (ultra DMA-66 ide Controller)

Option: enabled, Disabled

This option enables or disables onboard DMA-66 controllers. If you want to use a DMA-66 device, only
Set it to enable. If the IDE device on the motherboard does not support the DMA-66 or is faulty
Situation often occurs on some compatible motherboard) You can set it to disable, this will not only avoid problems
And can even reduce the startup time.
6. USB controller)

Option: enabled, Disabled

It is mainly used to enable or disable USB (Universal Serial Bus). After it is enabled, you can use a USB device. If there is no USB device, you should disable this option, this not only reduces system conflicts, but also saves an IRQ for other devices.
7. USB keyboard support (USB keyboard Support)

Option: enabled, Disabled

After enabling this option, you can use the USB keyboard. If not, disable it.
8. USB keyboard support via (supported by USB keyboard)

Option: OS, BIOS
With this option, you can choose to use the operating system or BIOS to support the USB keyboard. If Windows 98 is used, choose OS. In this way, there will be more functions in the USB keyboard Win98. If you are still using a MS-DOS, select the bios and use the USB keyboard directly without loading the driver.
9. init display first (initialization display type)

Option: AGP, PCI

This feature is especially useful when you have two graphics cards and only one monitor, because you can choose to use the display using the AGP or PCI graphics card through settings. If you only have one video card, you can choose the current video card type to reduce the start time.
10. Options: 8 MHz, 12 MHz, and 16 MHz

This function is used to adjust the keyboard frequency to increase the response speed. If you select 16 MHz, the response speed will be faster. However, if the keyboard cannot withstand such a high frequency, it may become unstable or cannot be initialized, and the frequency should be lowered.
11. Power on function (power on Mode)

Options: button only, keyboard 98, hot key, mouse left, and mouse right

This option allows you to boot in any of the following ways. In general, it is set to button only (only enable key is used). Other options are 98 key, hot key, and mouse. It is worth noting that if you are using a com or USB interface, the mouse cannot be turned on, because only the PS/2 interface mouse supports the mouse boot function, the mouse of both the COM interface and the USB interface does not support this function. Of course, some 'mouse 'of PS/2 may have some compatibility problems that may cause the machine to fail, this is as long as you set the option to only use the key. For keyboard 98 items, you only need to use the wake-up key on the keyboard to start up after Win98 is installed. Of course, the old keyboard can only define its own hot key.
12. onboard FDD controller (on-board soft Drive Controller)

Option: enabled, Disabled

This function is mainly used to enable or disable the on-board drive controller. By default, the on-board floppy controller is enabled. If other floppy controllers are used or there is no floppy disk at all, you can disable this option to save the next IRQ.
13. onboard serial port 1/2 (onboard serial port)

Options: Disabled, 3f8h/irq4, 2f8h/irq3, 3e8h/irq4, 2e8h/irq3, 3f8h/irq10, 2f8h/irq11, 3e8h/irq10, 2e8h/irq11, auto

This feature allows you to manually configure the I/O address and IRQ of the serial port. Generally, you can set this option to auto to enable the BIOS to automatically set the I/O address and IRQ. However, if some of your devices conflict with the addresses occupied by the serial port, You can manually set them here to solve the problem. However, users who do not use the serial port can choose disable here to save an IRQ.
14. onboard parallel port (on-board parallel port)

Options: 3bch/irq7, 278 H/irq5, 378 H/irq7, Disabled

This function allows you to manually configure the I/O address and IRQ of the parallel port. In most cases, the default I/o address 378 H and IRQ 7 work normally. If your parallel port conflicts with other devices, you can manually configure other I/O addresses and IRQ for the parallel port to solve the problem.
15. Parallel Port mode (parallel port Mode)

Options: ECP, EPP, ECP + EPP, normal (SPP)

This function is usually in the parallel port option. If you disable the onboard serial port, this function will usually disappear or become unavailable. There are four modes to choose from. The default value is normal (SPP). The spp mode has the best compatibility with other parallel port devices, but the speed is also the slowest. In addition, there are two other optional modes: ECP (enhanced comport) and EPP (enhanced parallel port ). Because the DMA protocol is used for ECP, the maximum data transmission rate can reach 2.5 Mbits/s, which is suitable for one-way massive data transmission with interface devices (such as using scanners or printers ), EPP is suitable for mutual data transmission with Interface Devices (for example, some drivers connected to the parallel port ). However, for users who do not know which mode to select, the BIOS provides the ECP + EPP mode, that is, the BIOS automatically selects one of the above two modes (of course, this requires your interface device to support one of the above two modes.) However, this often fails to achieve the highest performance. Therefore, in order to improve the transmission speed of the interface device, it is best to select one of the modes correctly.
16. ECP mode use DMA (using DMA in ECP Mode)

Option: Channel 1, Channel 3

This function also belongs to the parallel port option. Channel 3 is usually selected. If the device has a conflict, you can select Channel 1.
17. EPP mode select (EPP mode selection)

Option: EPP 1.7, EPP 1.9

This function is also in the parallel port option. You can use this option to select the EPP transmission mode version. Of course, although these two options are obviously different, however, based on past experience, the higher the version, the more perfect it is. Otherwise, how can the software be upgraded every day? Therefore, select EPP 1.9.

18. ut clock select (select the keyboard input clock frequency)

(4). PNP/PCI configuration
1. pnp OS installed (plug-and-play OS installed)

Option: Yes, no

If you are using a plug-and-play operating system like Win9x, set this option to yes so that the operating system can manage all the device resources, if no is selected, the BIOS automatically manages the device resources. Note that Linux users who use the ISA card should pay attention to this because most Linux versions come with a tool called isapnptools to configure the ISA card. If this option is set to no, the BIOS will automatically configure the resources of the ISA card, and isapnptools will also help the ISA card to configure resources, so there may be conflicts between the two. The solution is to set the pnp OS installed to yes so that isapnptools can automatically help the ISA card configure resources. The problem may be solved.
2. Force update escd/Reset configuration data (Force update escd/Reset configuration data)

Option: enabled, Disabled

Escd (extended system configuration data) is a plug-and-play BIOS function used to store information about the system IRQ, DMA, I/O, and memory. This option is usually set to disable. However, if the new adapter you have installed causes resource conflicts (for example, the system cannot be started normally), you should re-enable this option so that the BIOS can be re-configured with plug-and-play devices, to solve the conflict between new devices. The BIOS will automatically set this option to disable at the next restart.
3. resource controlled by (resource control usage)

Option: auto, manual

Generally, you should set auto to enable the BIOS to automatically configure IRQ and DMA resources for plug-and-play devices. Unless the BIOS cannot automatically allocate resources to devices, you should select manual to manually assign IRQ and DMA to each device.
4. Assign IRQ for VGA (assign IRQ to VGA)

Option: enabled, Disabled

Currently, many 3D acceleration cards need to be assigned an IRQ to work properly. If they are set to disable, these graphics cards may not work properly or their performance may be compromised. However, some low-end video cards can work without IRQ, so unless you urgently need an IRQ, you should set this option to enable.
5. Assign IRQ for USB (allocate IRQ to USB)

Option: enabled, Disabled

This function is used to enable or disable USB devices. If there is no USB device, set this option to disable to save an IRQ for other devices.
6. pirq_0 use IRQ No .~ Pirq_3 use IRQ No. (pirq_0 uses the IRQ Number ~ Use the IRQ Number for pirq_3)

Options: auto, 3, 4, 5, 7, 9, 10, 11, 12, 14, 15

In this option, you can manually specify IRQ for devices installed on the AGP and PCI bus. This feature is particularly useful when you try to mount the hard disk to another host and do not want to reinstall the operating system to detect IRQ. In this case, you only need to remember the original IRQ and then manually specify the new device with the original IRQ Number in the BIOS.

Overview
By understanding the various BIOS options, we can not only optimize BIOS settings, but also speed up the system, and often solve some system problems that cannot be solved in windows.
BiOS settings are closely related to the performance and efficiency of the computer system. If properly configured, the computer performance can be improved; otherwise, the computer will not be able to play its due functions. So it is not very confident, so we recommend that you do not change its settings.