Troubleshooted Video Card, this must be a BIOS prob?

A7N8X Deluxe motherboard
w/ amd athlon 2500+
radeon 9800 pro videocard
DVI Dell Ultrasharp flat panel

One month ago i started my comp and there were red lines that look like this w/ the regular screen showing but the lines through it.

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So i changed the Color settings on the ATI tray icon from 16 BPP to 32 BPP. I've used the 32 BPP since.

But Call of Duty and CS: Source don't work. Wacked out glitch vanashing point in the middle of the screen drawing images away or to that point.
There's occasional screen blinks for 3 seconds.
My dell ball mouse isn't recognized all the time and my external harddrive is recognized 4 of 5 times when plugged in.

I've downloaded BIOS stuff and have probably muffed everything up by trying to install BIOS updates and driver stuff.

Please help
Thanks, Andrew A
Indianapolis