Problems enabling SLI on two graphics cards that are not identical

by on August 2, 2009

Q: I recently installed two GPU’s in my computer running 64 bit Windows XP and was hoping to run them in SLI configuration. One is a GeForce 8600GT 512MB manufactured by KFA2 and the other is a GeForce 8600GT manufactured by Nvidia. After hooking everything up I found there were no SLI options or multi-GPU settings at all in the Nvidia control panel.

My computer has detected both GPU’s so there is no discernible hardware problem. All the latest drivers have been installed. After digging around for hours in the control panel I found the system information, which told me that my two cards have slightly different clock speeds and various other technical differences. Is this the reason I am not able to enable SLI? Is there any way around this?

A: After reviewing your link to GPU-Z data we can determine that the ram does not match in the cards. So while the card has the correct GPU for an 8600GT card it does is a 128MB card. It is a very stripped down model and is the reason you cannot enable SLI.

This should be a warning for anyone wanting to enable SLI. Make sure you double check all the information related to your graphic cards to make sure that they are identical.

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