Boot disk failure, WTF?

Ok, this is the second time in 2 months that this has happened to me. I go to
start up my sons computer and it doesnt boot and I get the error "boot disk
failure" The hd (maxtor 80 gig) is found in bios no problem. If I use the
maxtor floppy it claims that my HD is not set up for use yet. It will list an
"unknown partition" If I boot to a win xp disk. My info seems to be there
(something is) but it seems like the MBR is wiped clean or something. The drive
passes all maxtor drive tests. Could the motherboard be causing this? A few
months back I switched out a bad k7s5a for another ecs board. If I remove the
drive and slave it in another system it still comes up as unknown partition.
Its not a virus because the machine was just totally scanned and spyware
cleaned the night before. And yes it worked fine this morning. My main concern
is keeping this from happening again. Its a major pita and my son is gonna be
pissed because all of his massive gaming stuff is now lost, again. Should I
replace the drive or the motherboard? Both? Any other ideas? Oh, its winxp pro
with sp1 installed. Any ideas on retreiving the data that dont cost a fortune
appreciated also. Tia.

I think ParitionMagic 8.0 has some sort of bootable option that can
reformat your drive without data loss. This shouldn't cost more than
a new HDD. In fact, I think if you enter a couple of random letters
at the registration code screen in the shareware version it will
operate as normal.
Hope that helps,
-Hukuis