Computer Not Recognizing 2nd Graphics Card

[Stza]

Hi all, I hope this isn't a dumb question... i figured it would be an easy answer to find, but i haven't had any luck.

Anyway, I just bought a 2nd 8800gt to run in SLI with my old one. I've installed both, but when I turn my computer on I it doesnt recognize the 2nd card.

What I've Done:
-Made sure that both cards work (ran them both independently, one at a time)
-Made sure they are firmly seated in their PCI-e slots
-The fans on both cards are spinning when they are installed and the computer is turned on, so they have power.

-Attached the bridge correctly and firmly (The little arrow on the bridge matches up with the little arrows on the cards).
-Pulled out my motherboard's "SLI Switch Card", turned it around and plugged it in so that it was set to "SLI MODE (x8/x8)".

I've read a bunch of Q/A's, with mixed answers: a) I should be able to just boot into windows and it will detect both cards automatically, and b) others said I need to change some settings in the BIO's.
-if a) is true, I guess I haven't installed correctly or maybe there is some software issue on my computer? any tips on what to look for?
-if b) is the case, could anyone point out which BIOS settings ill need to edit, and what to set them to? I've never done much work with BIOS before. I would really appreciate the help.

Thanks in advance to anyone that has suggestions/recommendations/questions, I really appreciate your time and help!


System info in case it helps:
-Windows Vista Home Premium, 32bit
-Motherboard: MSI P6N SLI Platinum LGA 775 NVIDIA nForce 650i SLI ATX Intel Motherboard
-Power Supply: ETASIS ET850 True 850W, Max 950W ATX12V / EPS12V SLI Certified CrossFire Ready Active PFC Power Supply
-CPU: Core2Quad @ 2.4ghz
-MEMORY: 4GB (3 really, w/ 32 bit OS).

 

[JackNaylorPE]

Whenever doing GFX Card changes, i always uninstall drivers ....change / add cards .... reinstall drivers.

 

[rolli59]

check every thing in your bios there is nothing to be scared of you can always exit bios without saving changes so everything will be the same as before.

 

[redwolfexr]

Try running them without SLI, go into the Device Manager and see if both cards are there.

I ran a pair of 8800GTS at one point, but I was driving separate monitors with mine.

If you can see both cards in Device manager then try to move your display between them and see if they both are working. After that check in the NVidia manager to see if they both are showing in multi-GPU panel.

One other thing, are they both EXACTLY the same version of the cad?

 

[Stza]

I'm uninstalling/reinstalling the display drivers now to see if that helps.

Both cards are the same model (8800gt)and have the same amount of memory, clock speeds, etc, but are different brands. Their specs can be found here:
-Old Card: http://www.newegg.com/Product/Product.aspx?Item=N82E16814150252
-New Card: http://www.newegg.com/Product/Product.aspx?Item=N82E16814133291
Are the differing brands a problem?

If upgrading the display drivers doesn't help, I'll try looking through the bios... but what should I be looking for, exactly? something with the letters "SLI" in it?

thanks for the replies all, keep them coming!

 

[Stza]

Well, upgrading the display drivers didn't help (couldnt have hurt though ) and I looked through everything in the bios and didnt see anything mentioning SLI.

I'll try loading it up with both cards installed, but with the "SLI Switch Card" turned to non-SLI mode and see if the computer recognizes both cards.

Any other segestions/pointers?

 

[rolli59]

Have you tried the manual. http://www.msi.com/index.php?func=downloaddetail&type=manual&maincat_no=1&prod_no=1140

 

[redwolfexr]

They DO have to be the same brand for SLI.

I was going to SLI my 280GTX and had no luck finding the specific card at a reasonable price -- I bought 2 nice Samsung 23" displays instead. Then I went and added a 23" DP monitor and a 5870 when they were available.

Your PC is probably seeing both cards, but they cannot SLI since their manufafacturer/model codes are not compatible.

edit: one other comment, SOME cards are compatible that are similar boards from the same manufacturer. I had EVGA and there were a few possible options, but its not well documented. The card makers tech forums are a great resourse for taht sort of thing.

 

[Mousemonkey]

They DO have to be the same brand for SLI.

I was going to SLI my 280GTX and had no luck finding the specific card at a reasonable price -- I bought 2 nice Samsung 23" displays instead. Then I went and added a 23" DP monitor and a 5870 when they were available.

Your PC is probably seeing both cards, but they cannot SLI since their manufafacturer/model codes are not compatible.

edit: one other comment, SOME cards are compatible that are similar boards from the same manufacturer. I had EVGA and there were a few possible options, but its not well documented. The card makers tech forums are a great resourse for taht sort of thing.

They do NOT have to be the same brand, I've run Asus and XFX cards together in SLi.

 

[redwolfexr]

Hmm, someone lied to me then.

Not the first time. I know that I couldn't find a GTX280 and ended up deciding to wait for the 5000s.