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I have a problem with my graphic card. When I am playing games on my computer, I have a weird image display:

enter image description here

And the game just freezes and it becomes impossible to play. I tried to find answers by googling but my research was irrelevant. I only find this website:, and based on it, it seems that the problem comes from my gpu card. They also provide solutions to underclock my graphic card but my problem is how to choose the correct values for underclocking. I am a newbie and I don't want to make a mistake. Can someone tell me how to do this?

Here is my operating system/hardware:

  • Operating System: Windows 7
  • Professional, 32-bit DirectX
  • version: 11.0 GPU
  • processor: GeForce 7900 GS Driver
  • version: 260.99 Core clock: 450 MHz
  • Memory clock: 660 MHz (1320 MHz data rate)
  • Memory interface: 256-bit
  • Total available graphics memory: 1535 MB
  • Dedicated video memory: 256 MB
  • GDDR3 System video memory: 0 MB
  • Shared system memory: 1279 MB
  • Video BIOS version:
  • IRQ: 16
  • Bus: PCI Express x16
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I you haven't already done so, clean the graphic card and apply new thermal paste if you know how to do so. Also please download GPU-Z, install it and run it. Go to the sensors tab, then select »Log to file« option. Minimize the program and start the game. Play it until the problem appears and post the resulting log file here. This way we may be able to see if the card is overheating. – AndrejaKo May 3 '11 at 19:56
Also if you don't have an idea how to start downclocking, lower the processor and memory clock of the card by some 5% to 10% at first and then keep lowering it by say 1% until the problems go away. When the problems do go away, try increasing the clocks by 1% until they appear again. This way, you'll know the correct maximum safe values for clock. Also note that you may need to lower memory and processor clock of the card by different percentage. – AndrejaKo May 3 '11 at 20:03
another interesting thing would be to research which type of error is caused by overheating memory and which by overheating graphics processor. If I remember correctly (and I'm not 100% sure, so do some independent research on that), the broad areas which appear green are results of overheating memory and the little red dots are results of overheating processor, but as I said, I'm not sure. You can use the problem type to determine when you set the correct frequency for memory and for processor. – AndrejaKo May 3 '11 at 20:05
My Nvidia graphics card also went nuts when I played this game!! Could it be the game causing some problems? – wizlog Aug 31 '11 at 17:51
You're not going to hurt a graphics card by UNDERclocking it. You can usually underclock at least 2 things: the video memory and the GPU core. Underclocking the memory may lead to a distorted display because the memory can't keep up with the display, but won't hurt anything. – LawrenceC Apr 25 '12 at 13:33
up vote 6 down vote accepted

I personally use EVGA Precision to down clock my gt335 to play older games (DX9 issue on the m11x). However I suspect that you may have more luck with a simple driver update. That card is a little old so if problems persist it is definitely worth an upgrade, 30-50 bucks can give you a 2-3x preformance increase.

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