Can't enable SLI and second vidya card isn't being detected.

Thathomelessguy

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Nov 4, 2009
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alright, so I've got a problem. I just got two GeForce 9600 GT 2GB, however my computer is only detecting one. I have an xfx750a mobo, amd 64 4000 and 1gb DDR2 memory, also have a modxstream-pro 700w PSU.
I also enabled SLI in BIOS. No option for enabling SLI in the nvidia control panel.
 
Do you have a 64-bit Operating System?

A 32-bit Operating System has a 4GB limit which refers to its Memory Map. It can only address or "talk to" up to 4GB of hardware. Your 1GB of RAM drops this down to 3GB and your first 2GB card drops this down to 1GB left out of which your computer uses at least half of that for other hardware.

You can NOT run two, 2GB video cards without a 64-bit Operating System.

(FYI, a 9600GT in reality can't use above 512MB for any existing games so the added Video RAM is consuming energy but not really being uses. Sorry.)

You may have another problem but what I mentioned is absolute fact.

If you upgrade to Windows 7 x64 (OEM) you should get more RAM. 3GB or 4GB is fine.
 
Well, I am not sure what your exact issue is, but I once had a similar problem, except my SLI worked before. It was on an A8N-SLI Deluxe, and one day it decided to only intermittently (very rarely, less than 10% at first, then never) detect the second card. I sent the board back to Asus and they fixed it (unfortunately I am not certain of what exactly they had to fix, as they were not specific, but all I do know is that some part of the board did go bad and had to be replaced).
 

cygone

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Oct 30, 2009
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Yes u can run 2bg of video ram on a 32bit OS, I know that as I am running 3x896 mb absolutly fine.

I had the same issue when i went from 2sli to 3sli.

I assume u have the SLI bridge installed?

What version of nV drivers are you using?

1gb ram ?

U really dont need to bother, sell a video card and buy more RAM!
 


System RAM and video are not the same thing and more importantly 2x 2GB cards = 2GB not 4GB
 
Memory Map:

No, System Memory and Video Memory are not the same thing. I agree. But both are part of the Memory Map, and in a 32-bit system the maximum is 4GB. The 4GB limit INCLUDES the System Memory and Video memory (and a few other things).

I know that you have an EFFECTIVE use of 2GB when you have two, 2GB cards because of the way that the VRAM is "cloned." I would think that Windows would still have the VRAM mapped to a total of 4GB in the Memory Map (if possible).

Also, I don't believe you have to be running in Crossfire/SLI just because you have two cards.

I'm pretty sure that Windows needs 4GB in the Memory Map for two, 2GB cards.