Removable hard drive cannot read exclude one example

Today, the size of a single file is growing, hundreds of trillion or even a few GB of capacity, the ordinary flash drive has been unable to meet the needs of users. As prices continue to fall, the mobile hard disk is more and more favored by users, large storage capacity and better portable mobility, data sharing between users, provides convenience. Mobile hard drives often encounter problems of this or that kind in everyday use. Sometimes it can be used on its own machine, but it can't be recognized on other computers. What's even more depressing is that when the data transfer process is prompting for read and write failure, which results in the inability to store files on a mobile hard drive, this situation often occurs when storing large volumes of files, so how do we solve this situation?

Some time ago, my friend borrowed a mobile hard drive to get a copy of the movie. The removable hard drive can be correctly identified on his computer, copying some small files is not a problem, but in a 4G of the United States to the past, error message: "Read and write cache failed." So try to copy a movie from the mobile hard drive, but not fail, but rather slow, less than 400 trillion of movies for nearly 10 minutes. After reseating, the computer will prompt "The mobile hard disk is high speed 2.0, my interface is not high Speed 2.0", after accessing the larger capacity of the data still appear the wrong hint. Restart the computer, sometimes the normal copy, but the speed is very slow, from the computer 4G to the past, prompted to more than 90 minutes, sometimes the same prompts, can not be copied. And I've never had a problem on my own computer. No matter how big the cuff is not a problem, the speed is also very fast.

The main reason for this inability to read or write too slowly there are three kinds: one is the USB interface of the computer or the USB interface standard of the mobile hard disk is 1.1, or the USB interface standard is 2.0 but the quality is poor; the second is the power supply of the USB interface; The motherboard USB driver is not installed ( Often occurs in Windows 2000 or Windows XP SP1) or installation errors;

According to friends, his PS/2 handle is USB interface, and in the use of no problems occurred. Carefully check the friend's computer, found using the Gigabyte 848 chipset motherboard, the South Bridge chipset for ICH5, it should be said that ICH5 's South Bridge chip has provided support for USB2.0, but it must be noted that even the USB2.0 interface, there are two different specifications. One is USB2.0 high speed, and the other is USB2.0 full speed. The former, we often use the USB2.0, the latter, in fact, is USB1.1. Because the USB interface looks exactly the same, there is no difference, and my mobile hard disk USB interface is fully compliant with the 2.0 standard, because your computer is using the USB1.1 specification, it will appear that the copy speed is very slow, in the insert will only prompt "mobile hard drive is high speed 2.0 My interface is not a high-speed 2.0 ".

Mobile hard disk with high-speed 2.0 copy, read faster than 25m/s, write faster than 15m/s, generally faster than this, this is the lowest standard. and USB1.1 or called USB2.0 Full speed copy speed generally does not exceed the 1.5m/s, so the speed of the transmission speed will be particularly slow when used. Through the friend Computer Bridge chip careful examination, found that with the ich5r, can be said ich5r fully support the USB2.0 standard, and is the real USB2.0 high speed. So what's the reason? My mobile hard disk is not a problem, USB interface is also 2.0 of the specification, will not be due to the cause of the virus?

By installing the latest antivirus to a friend's computer for a full antivirus, the problem is still unresolved. The problem with the driver is excluded because the friend is installing the Windows XP+SP2 version. What exactly is the problem? Insufficient power supply is also unlikely, because in order to solve the problem, the mobile hard drive has been a separate power supply. Is there a problem with the front USB port of the chassis? The mobile hard drive is then plugged directly into the chassis back motherboard to provide a USB interface. After the insertion, the system successfully detected the USB device, and did not appear "mobile hard disk is high-speed 2.0 of my interface is not high speed 2.0" hint, try to put some hundreds of trillion articles into the mobile hard drive, the speed is quite fast, so the problem is basically resolved. Originally, the main cause of the problem is due to some inferior chassis, in order to facilitate the use of users, although also provide a front USB interface, but these USB interface cable and the quality of the circuit board is rather poor, resulting in file transfer occurs in the above problems.

In addition, this inability to read and write from the problem of the mobile hard disk often occurs. Sometimes due to mobile hard disk and motherboard power, there are three main reasons: First, the hard disk itself is too big problem: for example, the use of Hitachi or Samsung of some models of notebook hard disk, current up to 1A (known as the largest USB port 500ma=0.5a), if the motherboard power supply is not very good, Sometimes there is insufficient power supply. Second, some motherboards, power design "save" some modules, in extreme cases (although very few but still have, such as to 1 a mobile hard disk power supply) will be problematic. The third is the problem of mobile hard disk box: Even if the previous two kinds of cases exist, if the mobile hard disk box in the design of the circuit board, it is also possible, such as using high-end chips, using circuit compensation design, not only you use a large current hard disk, the motherboard power supply is sometimes not too, can be stable operation.

Therefore, in the mobile hard disk, if the box error too many times, please replace the mobile hard drive box as soon as possible, change the use of the United States Cypress isd300a1, cy7c68300a, cy7c6830310, Yang-Zhi technology ali M5642, nec de μpd720130, μpd720133, Century Livelihood and cs8818g, and other chips of the mobile hard disk box, generally changed the box is good. There is also a point, in the use of USB data extension cord, as far as possible to choose those quality products, but only the picture is cheap, and caused greater losses.