Installed new VGA, system will not boot

[jfutima]

I just upgrade a 9800gt to a 280-GTX and the system will post but will no longer boot to OS. I have three separate bootable hdd's with three OS's; Vista x64, XP 32, and Ubuntu 8.10. BIOS only recognizes two of the three (not the XP 32).

* I thought it might be a power problem so I dropped the 9800gt back in and had the same issue
* Diagnostic (Ultimate boot cd) would not recognize any of the drives.

Even if I fried one the other two should work. Any ideas on what could be wrong?

Thanks in advance.

Q6600, Asus P5K P35, 4G G-skill 800, 150g Raptor, 750g seagate, 500g Seagate.

 

[pinaplex]

what kind of PSU do you have? brand and wattage? maybe it got damaged when you put in the GTX?

 

[jfutima]

Its a PC Power 750watt.
Everything seems to power up ok even the harddrives, they just won't boot however.

 

[jfutima]

I did have a clean partition on the 500g that I was able to install XP on and get the system started up again. It looks like the 750g is a goner and I will see what I can do about repairing the 150g with Vista. That seems to be intact it just won't boot.

Oh well, thanks guys.