Symptoms of a Failing Graphics Card?

[moniker7]

I've got a 3 year old computer I built from parts, and recently I've been having some issues with it.

Initially, I plugged it into a bad power source and got a surge, (or this was the best guess I had), and had to replace the PSU in order to get the thing to turn on.

Now, whenever I turn it on, it has serious issues rendering video. It will fairly regularly get colored lines in the screen, and sometimes on windows I get a blue screen mentioning the file "atimdag.sys" which I believe is a system file related to the driver for it (its an ati card).

The monitor works fine, as I use it with other devices flawlessly.
I just barley replaced the PSU, so I can only assume it is okay.
My guess is that this is a video card issue, and i'm about to replace the video card, should I proceed with this step?


System Information:
Asus P5Q Deluxe Motherboard
Intel Core2Quad Q6600 2.4 GhZ x4
ATI Radeon HD4870 512 MB
600w Power Supply



Also, if you do suggest I replace the video card, which one should I go with? I've got $150 to spend on it, including shipping.
I'd like to go with an nVidia card this time, as they have better linux compatibility, and a number of features i'm interested in. Would the GTX 550 Ti Fermi be a good choice or is there a better one?

 

[scout_03]

would try first to uninstall the ati driver and reinstall with the latest one before getting a new card

 

[jiyung]

Check out the HD 6790. By the way, those colored lines are called artifacts, I heard you could fix it by baking the card... (Seriously.)

 

[Supernova1138]

By the way, those colored lines are called artifacts, I heard you could fix it by baking the card... (Seriously.)

Ah yes, the "oven hack". If you do go that route, make sure you do it in a very well ventilated area, toxic fumes are an issue if you want to bake the card. Another possibility is that the thermal paste on the card has degraded and is causing the RAM to overheat. Taking off the cooler, applying new thermal paste, and remounting the cooler will fix the card if it is a thermal issue. Try downloading GPU-Z and check the temperatures it reports for the various parts of the card.