Can I run Dual SLI on a 975x board? Asus P5W DH Deluxe?

crewxp

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Hey, my current video card is half bad... see my other thread link for more info about it, I have an ATI X1900 XTX card right now...


But I have an Asus P5w DH Deluxe mobo, which has a 975X chipset. It's advertise it supports Crossfire, but I think I want to go Nvidia for my next card.

I want to get a good card (as I'll be running my water cooling setup through the main video card).

And I want to run SLI or crossfire, with 4 monitors. I just got 2 new 24 inch's that I had won.

So, basically... is there any way to run SLI on my motherboard, even though it's a Crossfire motherboard? I know one year ago I read that it had driver problems with that. Do you even recommend it?

-Thanks
[CrewXp]
 

croc

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Nope. Sorry, if you want SLI you'll need an Nvidia based MB. It's a licensing issue, really, not a MB issue per se, but there it is.

On the other hand, V8Venom had a good thread about the 2900xt's (iGB variety) and the new catalyst drivers.
 

darkguset

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You actually can, through hacked NVIDIA drivers, can't remember the source, just google it. The bad thing is that they are quite old, 88.xx if i remember correctly. So... you better stick with crossfire or get a new board based on the NVIDIA chipset and go SLI.
 

croc

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And there are a few others, just as buggy. Didn't want to get the OP's hopes up, and didn't want to help trouble-shoot the resulting mess.... :sarcastic:
 
Well - The OP has an Intel chipset, which means Crossfire/ATI. As pointed out, there is software available on the web which would allow SLI on a Crossfire board. But to my knowledge it's not officially supported by anyone, buggy to begin with, and in a dual GPU world you will almost always need patches and/or software updates for each game you want to play.

So the 'supportable' answer to the question is "No, you can't run SLI because you don't have an nVidia chipset. But you *can* run Crossfire, which is ATI/Intel's way to accomplish the same thing.

Speaking of mainstream technology as it stands *right* now, know that because of current PCI bus limitations two video cards are most assuredly *not* twice as fast as one. Why? You get one X16 lane and one X4 lane, at best, and are FAR more likely to have X8 twice. You would need a brand new - and only available as of last week~ish - be well advised to wait until the BIOSs in these have matured some - Motherboard sporting an X38 chipset to get X16 times 2. That chipset only supports Crossfire - no SLI. Also - While you can have DDR2, the X38 chipset is optimized to run DDR3 Ram. Which is freaking expensive and only demonstrably better than DDR2 at very high clock rates. There are articles on this site covering this stuff should you care to delve deeper.


It's true that when splitting hairs at the highest level, nVidia's current cards are superior to ATI. But to be brutally honest, the difference is measured in 10's of Frames Per Second, at FPS rates which are already far higher than the human eye can ever hope to differentiate. Given the position you are in now, IMHO, your best value per dollar spent would be to buy a decent (not best) pair of 2900's, setting them up in Crossfire on the Mobo you have now, and calling it a done deal. If you really want SLI, you'll need to spring for a new Motherboard, as well as the pair of video cards.

But having said all that: Personally, I still think that a single, superior, GPU remains the best bet if price/performance means anything. And that means an nVidia 8800GTX or Ultra as of this writing. In My Very Humble, Mildly Cynical, and Jaded OPINION, the best use for Crossfire/SLI is to extend the life of the card you spent $500 on a couple years ago by pairing it with a twin for $250. You'll save yourself $250 towards your next build, since by the time the dual setup runs out of steam, you'll be at 4~6 years and will have to gut your case and rebuild from the bottom up anyhow. But that's just my $0.02, and you should feel perfectly free to ignore me on that.
 

CompuTronix

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To clarify, the 975X chipset has two lanes at 8X in Crossfire mode, while the 965X and P35 chipsets have one lane at 16X and one lane at 4X. Since graphics cards don't utilize the entire 16X bandwidth, the 975X chipset runs Crossfire quite well with dual 8X lanes. Also, Crossfire requires that one of the two cards must be a master.

Hope this helps,

Comp :sol:
 

Gravemind123

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The SLI drivers for 975X that are actually completely stable I think are 84.56 or something like that. They only handle up to 7950GT SLI if I recall(might do GX2 SLI also), so nothing with 8-series cards.