abit bios flash makes disks dissapear!

[Guest]

Configuration:

Abit KT7A-Raid Bios Level YH
AMD Athlon 1200, non o/c
Matrox G450
2 x Mushkin 256 High Performance Rev2 PC133 = 512 Mb
2 x Western Digital 200BB, on IDE 3 and IDE 4 NON-RAID
Asus 50x CDRom on IDE 2
Tdk CDRW 8-4-32 on IDE 1

Other components: sounblaster live, scsi-isa, modem, Network card, removed.

Windows ME
Norton Antivirus
Partitions defined and formatted with WD utility, later arranged with Partition Magic 7.0

Problem:

Flashed bios 64 according to instructions, both with abitfae and runme.
After flashing, hard disks attached to IDE 3 and 4 are not recognized at booting.
(these disks are not a RAID configuration)

Tried flashing 3R, same result.


Suspecting something wrong with HPT370 bios, I connected one of the disks to IDE 1.
Disk is still not recognized at boot.


Going back to YH brings everything back. Disks recognized both at the regular IDE channels and the HPT IDE 3 and 4.

What's happening?

 

[Guest]

Starting from the other end, I discovered in the Western Digital site a very simple recommendation: if drives are alone in an IDE controller, jumper as 'single', not as 'master'.
Abit bios YH tolerates both, but other Bios versions apparently do not.
So, when everything else fails, read the FAQs....a little embarrassing.
Thanks to all.