I just installed a new GeForce 6800 video card, but upon reboot the monitor will not display anything. Removal of the card causes the computer to run fine, but reinstalling the previous card causes the same problem. It gives only a single POST beep at startup and the computer sounds as if it's running properly (the keyboard and mouse respond as usual) but I can't get any sort of visual, any help?

Beep codes

Beep Codes

Beep codes

Consult your mobo manual and see what info it gives for 1 beep.

Make sure you have seated the graphics card correctly in the PC and check all cables.

take your small "watch" battery (aka cmos battery) out of your motherboard for a minute or 10. this will reset all the bios settings on your computer. dont worry this wont hurt it, just reset it, plug in your new card, then place the cmos battery in again, and boot up.
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