The card is:

NVIDIA GeForce 7800 GT
PCI express

it is about 15 months old now. I have never overclocked it, and never had any problem with the card whatsoever. Today, while in the middle of gaming random horizontal red lines started appearing on the screen and moving/flashing up and down the screen. i alt-F4d the game and it was doing it on my desktop as well, along with some grainy red dots appearing around the screen.

Temperature was my first thought, so I checked the card temperature: 65 C...well below the 115C threshold even tho 65 seemed a high. I checked my CPU temperature. 45C, also well below its threshold. Never the less I took the cover to my case off and used my compressed air to dust all the parts and fans and airways etc. Turned it back on and after about 10 minutes it started doing it again.

I am pretty sure it is not the monitor, because when something is loading, or the computer is starting up, any time the screen 'goes black' for a second in transition, all the lines disappear, and reappear again when there is an image to display (Altho i suppose there is still a chance it would be the monitor).

Any advice/tips/previous experience?

Thanks in advance

And PS, im about to hook up a different monitor and try using onboard video with my current monitor as well to try and isolate the problem for sure


[Edited on March 24, 2007 at 6:34 PM. Reason : ]

3/24/2007 6:13:34 PM

[Edited on March 24, 2007 at 6:53 PM. Reason : bus artifacts:http://www.playtool.com/pages/artifacts/artifacts.html]

3/24/2007 6:52:57 PM

yea artifacts was something else that crossed my mind, but I talked to a few of my friends who had PCIE cards without after market heatsinks and they and I had never seen it happen on a PCIe card (even tho i know its possible)

guess i might be getting a new heatsink and hope that solves the problem?

[Edited on March 24, 2007 at 7:17 PM. Reason : ]

3/24/2007 7:04:35 PM

What were the results of checking the monitor and what type of monitor is it?

3/24/2007 8:05:18 PM

It's not your monitor. A screencap wouldn't show a monitor issue.

[Edited on March 24, 2007 at 9:35 PM. Reason : .]

3/24/2007 9:35:25 PM

^ yes i completely understand that heh . I had not taken a screenshot yet when i made the post (and still havent).

i should have thought to take a SS as a test tho instead. but i definitely found that it was the video card after trying a few different setups. Although tonight it is not doing it (i have an extra fan tonight blowing directly on top of the card).

gaming under heavy load today it has been around 65-70C. definitely higher than it used to be when i first got it..but not something i would be extremely worried about if i hadnt seen any problems. Still wondering if installing a heat sink to knock it down a bit would prevent this from happening again. The only thing i can think at this point is that it must have been the heat as it hasnt done it yet tonight with normal computer usage and with the fan blowing on it.

3/24/2007 10:29:43 PM

so with a lot of AC on and an extra fan blowing directly on the card it was running at around mid 50C tonight (testing it gaming). worked fine for a couple hours then it happened again and a lot more lines etc. and now when the PC turns on it does it during the startup screens and everything.

52C was the Temp of the card when i checked before turning off the PC. i really cant imagine a card overheating at 52C

any other ideas before i buy a heatsink?

[Edited on March 25, 2007 at 3:01 AM. Reason : ]

3/25/2007 2:59:27 AM

I don't think a heatsink is going to do anything for you except void whatever warranty you might still have.

When you say it's doing it during the "startup screens" do you mean the Windows startup screens or the BIOS screens? If the former, then uninstall/reinstall your video card drivers and DirectX. If the latter, go check your card's warranty information.

3/25/2007 3:15:01 AM

sounds to me like your GPU's heatsink isn't making contact anymore.

If you've still got a warranty, get the card replaced/fixed. If you don't have warranty on it, buy a new heatsink and make sure you install it right.

3/26/2007 8:49:41 AM