64bit, random crashes, bios doesnt detect hard drive

[Soup0rman]

I've been having a continual problem with a comp I bought, it has vista 64 bit on it, but sometimes it will randomly restart and will be unable to detect my master (sata) harddrive in bios so obviously it fails to boot. the secondary hd will appear but it has no OS loaded on it

The hard drive has been replaced twice by the manufacturer (gateway, its a model gt 5676)
Only thing that has been changed on the original config of the computer is I put in a ati HD3870 and a larger power supply,

Gateway's only solution to this was for me to test the drives with gwscan, write 00's and reinstall everything which I did , it will work fine for a few days then this will happen again and Im only occasionally able to get into windows on the comp

Windows startup repair doesn't work as it doesn't detect my HD 80% of the time or so

now they want me to send it in at my expense for them to "Test" even thought they haven't been able to figure out the problem yet

Anyone have any ideas or know of any hotfixes? thanks a ton

 

[notherdude]

Since you have tried two new drives I strongly suspect the problem is with their motherboard. The fact that the BIOS often fails to detect it is a very strong clue that it has nothing to do with Vista or with software. I would push for them to fix or replace.

Short of sending it back All I could suggest is trying the HD with a different cable and on a different SATA port. Since the secondary drive always seems to get detected try using your main drive on that cable and on that port.