I have a m9700 with dual 7900 gs cards, I'm just wondering how SLI affects your computer. When I enable SLI it slows games and other apps by about 5-10 fps at the least. I've been asking for help for a while now but after just recently realising alienware had released the official vista drivers for sli, im worrying there might be a problem with one of my cards. I was going to call alienware back in october, but i remembered that I was using unofficial drivers for the SLI so I decided to just wait it out. After now installing the official drivers, I'm getting the same result as before. I've looked around quite a lot since before and there are some people saying It's because the single core processor bottlenecks the dual cards making it basicaly the same as using a single. Anyone having any success at all?

Games have to be set up for SLI to work well with it, so depending on the game your results may be mixed.

Counter Strike Source for example runs the same on a single card as with SLI.

Most newer games you should see at least a 50% boost though in fps with SLI.

The best way to see if your second card is working is to run 3dMark 05 or 06 with a single card, then compare the result with SLI enabled.

I get mid 6000's with a single card in 3dMark05, 10,000 with SLI.

While the single core turion is likely the limiting factor in outright performance, at the time it was the only mobile processor that supported SLI. It does quite a good job though, and you should see a noticeable difference with SLI over a single card with the turion.

What video drivers are you using?

Right now I'm using 169.21 from laptopvideo2go.com.

To use those drivers, download the driver, and the modified INF file. Unzip the driver folder, then put the modified INF file into that driver folder. It'll ask you if you're sure you want to replace the INF file with the new INF file, click yes. Then install the driver and it should work fine.

I'm using XP, not Vista.

I called up Alienware today, told me to switch my graphics cards and test each one out on their own. My graphics cards are fine, odd thing is with SLI enabled *using laptopvideo2go vista drivers 169.25* my score went from 3600 using single to 4890. But the problem is it only renders every other frame. Like it'll render a frame and then go black and so on... with Split screen it only shows the top half of the screen. When i submit my results *sli ON* it says linked display adapters : no but in DXdiag it says approx total memory 1255... with Alienware drivers it's just the same performance give or take 5 fps with sli on and off. Also, how do I find out what motherboard I have in my computer. I'm more of an XP user and I can't seem to find it

im using 512MB graphics cards, 2.4gghz processor

The dropping of every other screen, or half of the screen in SLI means either one of your cards is bad, or the SLI bridge, cable, or chipset is bad... The signal from one of the cards isn't getting processed.

You tested the cards, so it's not that. Did Alienware offer to send you another cable? I think it's either the cable or the chipset on the motherboard. The motherboard is made for this platform by Arima. It's the W830-DA. Here's a link. You'll find it under their performance line.

Alienware is the only company that distributes this model in the US.

my computer was shipped with an extra SLI cable so i don't think it's that cause I've tried both. I'm going to call them again today and talk to them. The thing is with the Alienware drivers, none of this happens, and I see a increase in performance in 3Dmark06, from about a score of 3600 using 1 card to 4600 using alternate frame rendering, and I can see the entire screen, but in every game I've tried it goes down. Bioshock, COD4, UT3, Crysis, WOW, NFS pro street, every single one it goes down about 7,8 fps, but in 3Dmark06 it goes up. Bizarre.

Edit: hm, after running 3dmark06 again with SLI enabled, it's dropped back down to 3600, same as single. :/