I have a 3 year old Gateway FX6840-03e desktop with an ATI Radeon HD 5770 graphics, and I've updated the drivers recently. (The rest of the parts are stock as well; Intel i7 860, processor, 500w psu, 8gb memory etc.)
Lately, the video signal to my monitor will randomly cut out, and while the monitor and computer will stay on, the computer will become non-responsive and I have to restart it manually, after which the video will work again for a little while.
The card has been really loud lately, and seems to spool up randomly, regardless of if I'm gaming or just using the internet, or if the computer is just running idle.
While I was installing a fresh copy of Windows, I got a beep code (1 long, 2 short). I tried re-seating the graphics card, but it didn't change much.