I have a GA-7VT880L motherboard, which uses the VIA K880 chipset and
the VT8237 southbridge controller. I recently bought a pair of Maxtor
DiamondMax10 300GB SATA150 drives (type 6L300S0) to add as secondary
storage (keeping the existing IBM Deskstar PATA drive as the boot
device).

The problem I'm having is that the BIOS sometimes recognises the
drives, and sometimes doesn't. Sometimes it sees one, but not both;
sometimes it sees neither. It makes no difference whether I set the
SATA mode to IDE or RAID. I have updated the mobo BIOS to the latest
version (F10), but this makes no difference. When the drives are
recognised, they work correctly in Windows (2000 Pro SP3), but after a
while they sometimes "disappear". Last night the machine was running
for a couple of hours, then suddenly Windows reported that it couldn't
save to one of the disks. On reboot, the BIOS didn't see them.

I'm fairly sure this is not a Windows driver issue: it's the BIOS that
seems to have intermittent problems. Nor do I believe it's due to
overheating, as this problem can happen from cold. I considered the
possibility that the extra power requirements were putting the PSU over
the edge, but after disconnecting the main PATA drive and the CD drive,
the BIOS still sometimes didn't see the SATA drives, so I don't think
it's a power supply issue.

I'm using the SATA cables that came with the motherboard. It seems
unlikely that both disks and/or both cables could be faulty, so I'm
left with the view that there is something wrong with the motherboard
or BIOS. Other possibilities are that there is some weird
incompatibility between the VT8237 controller and these particular
Maxtor drives, or that maybe the SATA cables supplied with the mobo are
borderline quality-wise. I admit I don't know much about SATA - these
are the first ones I've ever tried to use. Has anyone else got SATA to
work properly on the GA-7VT880 mobo?