Software SLI? Can i do it?

[PP Mguire]

Well ive seen some things or 3 about modified drivers to SLI 2 different cards without a SLI bridge. Is this true? And can i effectively SLI a 7950GT and a 7600GS or 6600GT? If i can, would it be worth it?

[Toxcity]

I believe SLIing 2 cards is coming in SLI2.. or something like that.

I guess you will have to wait matey!

[Mr. Smith]

You can do it, mix cards, without the sli bridge. However, sli performance suffers without the bridge.

I put a link on here a while back but it was taken off...

For sli'ing two different cards, I think they have to be similar architecture - the example in the link is a 7300 and a 7600. They basically used RivaTuner to change the ID of the 7300 to match the 7600. This then tricked the system into thinking the 7300gt was a 7600gt.

The only draw back? The primary card has to be the lower performing one...

Instead of me paraphrasing from memory I'll dig up the link.

Linky

[Jim]

Originally Posted by name='PP Mguire'

Well ive seen some things or 3 about modified drivers to SLI 2 different cards without a SLI bridge. Is this true? And can i effectively SLI a 7950GT and a 7600GS or 6600GT? If i can, would it be worth it?

The official Nvidia drivers will already run SLI without a bridge. When this feature first came about there as a small performance hit, but i'm not sure if this has been ironed out now.

As for SLI'ing two different cards, afaik this can only be done if they have the same core. Cards with the same core but made by different manufacturers can be SLI'd, but until "SLI 2" comes out, I don't think you will be able to SLI cards with different cores.

Edit: Mr Smith beat me...and he's got the facts too

[FarFarAway]

The long and th4e short of it: it's not worth it

[Pyr0]

i've successfully sli'd a 256mb 7900gt and a 512mb 7950gt using official and hacked drivers, not sure how well it would work or even if it would work with cards that are so different tho

i used rivatuner to change the hardware id of the 7900gt in the primary pci-e slot to a 7950gt, a quick change of the registry value of Coolbits to 1A and a couple of reboots later and the SLI bubble popped up on my desktop

i've got a couple of different versions of the drivers that were patched to work on non-nvidia mobos here:

http://www.overclock247.com/pyr0/Intel%20SLi/

[PP Mguire]

So i can use official drivers and Rivatuner to trick a 7600GS (or GT, idk which one it is yet) to think its a 7950GT? Or do i deffinately need a 7900 series card to SLI with this 7950GT. I have a real SLI board (nf4 SLI-DR) and a SLI bridge if i need it. I just heard i guess from Mr Smith about the hacked drivers or w/e and got excited and wanted to try SLI. If it dosent work and like Kemp said isnt worth it then ill ditch the experiement and go back to the trusty ol X1900XTX.

[Pyr0]

i'm not certain what the outcome would be with a 7600, but it's easy enough to try

the card in the first pci-e slot is the one who's ID you will be able to change

if changing the 7600 to a 7950gt doesn't work, try changing the 7950gt to a 7600 (find the ID's from the nvidia display drivers nv4_disp.inf)

either way, if SLI enables, you will only be running at the slower cards speeds

it should work with the official drivers if using an SLI motherboard

[PP Mguire]

Well if thats the case (got SLI drivers and oficial SLI mobo) would 2 7600GTs be faster than my single 7950GT or X1900XTX? (hahah doubt it)

[Toxcity]

From my experience I would downgrade the faster card.

If you try to make the slower card run with bigger memory and so it will blue screen you.

Well thats what happened to me But you are using differnet cores and memory so be extra careful.

So yeah, Chnage the 7950 to the 7600.

Its the safest way!