Nvidia 7800 GS (sqealing motherboard)

I tried to install this card into my dads computer and take his Raedon 9550 to put in mine.

Basically when I put the 7800 GS (an AGP card) into his computer and switched it on, the computer did an obscene squealing sound. A sound I figure came from the speaker on the motherboard (ASRock KAUpgrade - 1689)... I dunno. Nothing was displaying and I don't recall whether or not the computer was booting up.

Anyway, is there any reason why this would happen?

When I then returned the card to my computer, the hard drives weren't booting up and also never got a signal on the monitor... But inexplicably, after 3 more tries of booting up this morning, it suddenly just kicked in and booted up without problems. We thought the card may have been fried when it was in my dads computer.

could be the motherboard didnt recognize the video card and l know that it will beep like that if there is not a card if it doesnt have integrated already.

Basically on gthe motherboard there is a round battery called the cmos battery. Take that out and it will reset the bios and then put the 7800gs in. Wait about 5 mins and then put the battery back into the board. Then boot her up/ Make sure that the card has the power connections hooked up

Well it did do some beeps as well in the background which maybe alerted me to the fact that it wasn't finding the video card... but it was the other squealing sound that I thought was strange. The only way to get the computer to stop squealing was to just switch it off.

I will be unable to try out your suggestion about the CMOS battery. Basically the swap had to be done yesterday or not at all (long story). But I was just curious..

Thanks for your insight though.

Are you sure you plugged the power molex in the back of the card?