China DOS Union

Urgent! Urgent! Urgent:
A 486 machine bought in 1996: Ocean 15C motherboard, CYRIX 5X86 120M CPU, 850M hard drive. During an upgrade in 1999, I made do with the 486's 850M hard drive and got hit by CIH once. After repairing it with KV300, the capacity showed as 812M.
Recently little D has been learning typing, so I wanted to put the 486 back into use. But now the hard drive can no longer install DOS622 (the installation stops halfway through the first floppy disk), and all that appears on the hard drive are some strange characters. But if I connect the hard drive to a P3 machine, it can be installed and used normally; once I put it back on the 486 machine, strange characters appear again. No virus was found when scanning. Urgently need an expert to point me out of this confusion.

Use DISKGEN to rebuild the partition table, repartition it, note that it should be FAT16 format, boot with a DOS boot disk, run FDISK /MBR, then try installing again.

What mode is being used in CMOS? It has to be set the same as when the partitioning was done for it to work normally.

How many years old is your DOS floppy disk? Can you be sure it still works?
Old motherboards with small hard drives have all kinds of problems, so it's better to honestly redo it on the original machine, starting from partitioning. As long as the hardware is fine, it should all be fine.
Also, floppy disks are very suspicious things. It's best to use hd or something like that to read it once first; if there's no problem, then use it to install.

Following the method provided by the friend in post #2, when using DISKGEN, at boot it says disk sector read error. The rebuild partition table command started running from 11:30 last night, and it still hasn't stopped now. The floppy drive keeps making creaking noises, and sector checking still hasn't finished. I've completely lost confidence.
Oh right, the mode used in coms is LBA. It's still that same hard drive; back in 96 I even hand-copied the BIOS parameters.
Sigh! Everyone please help, don't discourage me by telling me to throw the machine away. I'm poor.

LBA mode in cmos? Your hard drive is only 850M, no need to use LBA mode, right?
I suggest not using a floppy disk to install DOS6.22 anymore.
If it's for learning typing... the classic old English typing software was TT, and for Chinese Wubi there was WT, or Minglun Wubi Expert Speed Course. Now I recommend Wubi Express, it's easy to use and the interface is good too.
No need to repartition either.
Just boot the machine directly with a system boot disk (I recommend a win98 one), use DM to partition and format it (if your DM has to be kept on a floppy disk, then please use a good floppy to store it), then reboot the machine, and transfer the system files from the boot disk to the C drive (using the sys a: c: command). That should do it...
If you want somewhat better tools, I recommend wengier's Super DOS boot disk. Just copy the stuff inside to your hard drive... If it asks to overwrite some files, overwrite them if you can; if not, it doesn't really matter...

How about trying a low-level format??

Don't tell people to do a low-level format at the slightest thing, okay?
For this kind of dangerous operation that can damage the hard drive, people should be advised to use it cautiously.

I used DM to "double-regulate" the hard drive, just barely making do with it now. Thanks everyone for the good ideas. There are still lots of hassles; I finally managed to install a 95, but OFFICE can't be installed. This piece of junk should've been thrown away long ago.