China DOS Union

Strange, under the same circumstances, MS-DOS 7.1 suddenly can't recognize the external hard drive.

The same computer, the same external hard drive, and the same MS-DOS 7.10 CD. A few months ago, it successfully ghosted the entire disk of the computer to the external hard drive under DOS, but now it can't recognize the external hard drive under DOS no matter what. (Changed to another external hard drive, and both hard drives are normal in XP)

The brief hardware configuration of the computer is as follows
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Computer system: Dell Computer Corporation Dimension A100/A200
BIOS: Award Software International, Inc. R1.09
Motherboard: Mitac International Corporation Spiderman
Chipset: Intel 82810E 810e Host-Hub Interface and Memory Controller

It is estimated that it is due to insufficient power supply from the machine's USB port or the hard drive enclosure. Sometimes it can be recognized, and sometimes it cannot be recognized.

Yesterday, I simply spent a whole day messing around. I used a 10G laptop external hard drive enclosure, an 80G desktop hard drive enclosure, a USB flash drive, this Dell computer, and another Dell dual-core laptop to repeatedly test the issue of recognizing external hard drives under DOS.

When testing these three external storage devices on the desktop computer, MS-DOS 7.1 was used, while on the laptop, max-dos installed in the computer's boot options was used. It seems that both DOS systems use the panasonic program for recognizing external hard drives, but the test results are equally ridiculous.

Let me explain again. The 10G laptop external hard drive enclosure is powered by USB, and the 80G desktop hard drive enclosure is a Datalink enclosure, which is externally powered. All three external devices are USB 2.0.

The result is that no matter how I tinker, the three external devices cannot be recognized when booting in USB 2.0 (or 1.1) mode on both computers, let alone performing hard drive-to-hard drive Ghost. However, when using clean boot and entering Ghost, on both computers, the USB flash drive and the 10G laptop external hard drive enclosure can stably enter the hard drive-to-hard drive Ghost option, but connecting the 80G desktop hard drive enclosure always shows that there is only one hard drive in the system.

How did I successfully perform hard drive-to-hard drive Ghost with the 80G desktop hard drive enclosure under the same conditions last time? It's really a mystery! What's the matter with this ridiculous test result this time? Does it only prove that Ghost versions above 8.0 do have built-in recognition of external hard drives under DOS? I don't understand DOS technology well, and these mysteries can only be solved by you all here.

Anyway, I don't think USB can be as universally applicable as floppy disks yet.