Novice must SEE: uefi/bios switch between Chinese and English text detailed

Since the release of Win8, the new factory pre-installed win8/win8.1 computers are default in UEFI mode to start the operating system. Many friends want to change Win7 or XP, but the process is not smooth. This problem is caused not only by the operating system support for UEFI startup, but also by the fact that a win8/win8.1-pre-installed computer has a secure boot (one of UEFI's optional standards) that is limited to the built-in security boot key, Only Win8 and newer versions of the Windows family operating system can be authenticated through secure startup.

In the long run, UEFI is necessarily the mainstream development trend. However, since many users are still using Win7, especially the 32-bit Win7 (PCs are typically configured with 64-bit UEFI and can only boot 64-bit systems) and other low-level operating systems, the legacy bios+ UEFI BIOS Coexistence situation may need to continue for a longer period of time. Then, whether you want to try Uefi startup (if supported) in your old computer, or if you want to replace the pre-installed win8/8.1 system with another operating system, you need to familiarize yourself with the way the uefi/legacy BIOS switches. In this paper, we will use Lenovo Win8 computer as an example to compare the Chinese and English picture and combine the text to explain the several setting options that need to be noticed in the uefi/legacy switch process and their meanings. Small series of understanding of the level of limited, as the text in the understanding of the wrong place also hope to point out. ^_^

Tip: Different computer BIOS settings interface is not the same, but need to set the options are basically the same, but the choice of location will change. In addition to know how to operate, it is best to know why to do so, so you can do status quo!

First, press the computer power button (or reboot), when the system shut down the computer into the restart process repeatedly press the shortcut key to interrupt the computer to boot into the BIOS setup interface. Note: Different computers enter the BIOS of the shortcut keys are different, usually F1, F2, DEL, ESC and so on. The specific setup options are as follows:

1, OS optimized defaults system default optimization settings

In some computers pre-loaded with win8/8.1, this option is available, and computers that do not have a win8/8.1 pre-installed are not generally available. Switch to the Exit tab, as shown in the English image above, with the following image in Chinese. below) where it can be found:

The OS optimized defaults is a "top-level" setting option that, when turned on, automatically restores all relevant options (that is, each of the options described below) to the standard setting required by the pre-installed win8/8.1 default startup method, which is to turn on the uefi+ to open the security boot.

When you need to switch to UEFI: If only install win8/8.1 can choose to "open (Enable)", Other cases "off (Disable)";

When you need to switch to Legacy: "Close (Disable)" should be selected.

2. CSM Compatibility module setup

Switch to the Startup tab. The following figure

CSM (Compatibility support module) represents a compatible module that is designed to be compatible only with devices that work in legacy mode and operating systems that do not support or do not fully support UEFI. For example, at present, many independent video cards do not have GOP BIOS support, can not work in UEFI mode, at this time must be "open (enable)" CSM. Note that the CSM option is in conflict with the security boot (described below) on a computer configured with Class 2 type UEFI, and the two can only open one at a time.

When you need to switch to UEFI: it is recommended that you select "Close (Disable)" Only if you are installing win8/8.1 and that you need to turn on a secure boot, otherwise "open (enable)";

When you need to switch to legacy: Select Open (Enable).

3, Boot mode boot mode selection

This option is still on the Startup tab, boot mode (boot mode), which is the primary setup option when switching uefi/legacy BIOS. There are generally three options:

Auto (Auto): Automatically according to the order of the starting device list, priority to adopt UEFI mode;

UEFI only (UEFI only): Select the device with UEFI starting condition;

Legacy only (Legacy only): Select the device with Legacy starting condition;

Choose one or the other according to your needs.

4, Secure boot security boot settings

This option is not valid in legacy mode and does not need to be set. Safe Boot is an optional standard for UEFI, which is not available on some UEFI computers. A security-enabled motherboard is shipped with a built-in, reliable public key. This allows only software (systems) that have been signed with the corresponding private key to be loaded through the authentication of the built-in public key during the boot process. Malware cannot be authenticated and naturally cannot be loaded. Therefore, this will ensure the computer to start safe. UEFI does not specify a specific issuer of the public key, while on a computer preinstalled win8/8.1 Microsoft forces OEMs to adopt a safe boot standard and place Microsoft's own public key. Because the pre-installed win8/8.1 computer is safe to boot from the factory, the default is the "on" state, which leads to the inability to boot other operating systems, including Win7, by default (note: Other systems are currently authenticated), but users can choose to turn it off. Look at the specific setup options:

Switch to the Security tab, as shown below

Then turn on the Secure startup option settings, as shown below

Here are two options:

First, security boot (secure boot) option. If we want to install a system other than WIN8/WIN8.1/WIN10 in UEFI mode, we recommend that it be turned off. Also, be aware of the problems that CSM has in conflict with the security boot that was mentioned in the CSM option settings above. In view of this, usually we set it to "Off (Disable)", in the closed state, there is no need to consider the second setting option.

Second, reset to set mode/restore factory settings (reset to Setup mode/restore Factory Keys) option. This option clears or restores the built-in security startup key. Generally we do not need to set this option. If your computer is pre-installed with win8/8.1, you have changed the settings option, and now you want to restore the default settings (including starting a secure boot), you can restore the security startup key to the default value by this option.

These are some of the setup options you need to be aware of when uefi/legacy BIOS switching.