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Sli: Xfx 7900gt 256 & Evga 7950gt Ko 512

T

thebeephaha

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Can I mod the BIOS so they could work together? Or am I out of luck?

Reason is, I have a good 7900GT but its getting too weak for some games on its own and my 7950GT KO is having issues at its native clock speeds so I wanted to maybe clock it at the same speeds as the 7900GT but also SLI the two to make up for both cards deficiencies.
 
panchoman

panchoman

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they should be able to work together.. but they will run at 256 ram and the slowest speed of either cards.
 
T

thebeephaha

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Will I need to mod BIOS at all though? Or are the drivers smart enough to figure it out?
 
panchoman

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should be smart enough to figure it out :)
 
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Nope just tried it and I don't get the option to SLI... Using 169.21 drivers.

I also tried coolbits and set the value 18 (SLI Zone says to do this) to allow different RAM sizes in SLI config but that didn't help either.

Now I need to know, how else can I make this work? Can someone explain how to flash my 7950GT bios down to a 7900GT?
 
Last edited:
T

thebeephaha

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Software Windows 10 Pro 22H2
I figured out how to use nvflash and NiBiTor to flash and edit the bios, so first I tried copying my 7900GT bios to the 7950GT, this doesn't work entirely... The card "works" but the picture is garbled so I had to flash it back.

I tried the other way (7950GT bios to 7900GT card) but of course editing the clocks and voltages down so as to not damage the 7900GT and guess what? IT WORKS. My computer now sees TWO 7950GT cards, only difference being RAM amounts. (one has 256MB, one has 512MB)

I then edited both cards to have the same GPU/RAM clocks.

NOW... Since the computer thinks they are the same card minus RAM size differences how do I SLI them? The coolbits tweak to allow for different RAM amounts doesn't seem to do anything for me, so does anyone know where to get a hacked driver?
 
Last edited:
wolf

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weird, if it sees them as the same card then you should be able to do it quite easily.

but theres always the chance that the computer is smart enough to know they are still different cards.
 
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