280M SLI in linux. Any success?

There're only a couple of laptops out there with mobile 200M series graphics cards in SLI/Hybrid setup (Clevo M98, AW M17X).
So the question is how to make the SLI setup work in linux?
I'm running Ubuntu 9.10 and was able to turn on SLI with the latest 195.30 drivers and a lot of help from Stamatisx. Thanks again.
But when SLI is active the actual performance in 3D rendering decreases (at least on my system) making it impossible to play demanding games like Dragon Age.
So far I tried the following drivers:
185 - The best performance for a single card. (glxgears :42k). Can't run SLI.
190 - The performance with a single card is lower (glxgears:20K). SLI On gives messed up colors or reboot.
195 - Single card performance is ok (glxgears: 39k) SLI On makes very choppy rendering practically in all apps/games.

Has anyone succeeded in getting high performance out of SLI config in Linux?
Would appreciate your feedback and suggestions.

P.s> All glxgears runs where with the cards at power level 1 - NV_Clock=275Mhz; MemClock=301Mhz and I wasn't successful in setting the power level to 3 for the best performance.

 

Bump..
Ok, Let's forget about SLI - Does anyone have Linux on a laptop with a single GTX 280M card?

 

Hi, i really wish i could help, but i think you're not likely to find many ppl with sli vga config on laptops and even 'better' - with linux.
I wish, i could test your lappie with linux, well, i need bucks for other things .
Anyway, i think you could find better help for the SLI problem on some desktop forums, since there is the SLI config more likely to be had.

 

I figured out one of the causes of this issue:
For some reason the drivers are always (4 re-installs) installed incorrectly,
as you can see from the screenshot Nvidia X-server detects the cards as PCI express 8x instead of 16x... No idea why...

 

I am not sure if SLI will really improve much of anything in Linux.

 

First of all, I need the correct way to install the drivers and will welcome any suggestions. When a single card works fine we can tweak the SLI. I assure you it will improve the performance, I've seen plenty of successful benches on phoronix (all of them are desktop SLI/CF).

I tried the Ubuntu way, activating the drivers through the Hardware Drivers, and it's not perfect, only getting 30% of performance (good enough to run most of the games on medium details, but still).
So I downloaded the 185.18.14 driver (the one phoronix used for their Clevo with gtx280M and got impressive benches) but can't install it.

When I stop gdm and run the driver with sudo sh it wants to compile the nvidia kernel module....but fails
What prerequisites do I need to install to be able to build it?
What do I miss here?

 

maybe the sli is already working. reason why i say that is because it is showing it that is in express 8x instead of 16x. on the windows side gpuz will show both cards and and they both say 8x on the pci express side.

 

Ubuntu has a very easy facility for installing the nVidia proprietary drivers, which is the recommended method for installing them. It's described here and the basic instructions are;

Also

However, if you're trying to install the nVidia drivers manually then you need to make sure you read through this howto, and make sure you have the requisite Ubuntu components installed. At the minimum they are;

Code:

sudo apt-get install build-essential linux-headers-`uname -r`

After you install those components you should be able to download the nVidia drivers from the nVidia website and run their installer to install the drivers on your system. Again this is NOT the recommended method for installing the nVidia drivers under Ubuntu. One reason is described on the Ubuntu BinaryHowto/Nvidia page;

However, just installing the nVidia driver does not enable SLI. You need to modify your xorg.conf file, under the Device section for the nVidia device, and add;

Code:

Option "MultiGPU" "Auto"
Option "SLI" "Auto"

as described in this nVidia documentation chapter. You'll note that from that chapter that you can also run the command line tool, nvidia-xconfig (as root, or with sudo), with the appropriate command line switches, to insert the configuration line into your xorg.conf file, for you. All of the switches for the MultiGPU and SLI options, are listed in this nVidia appendix a little more than halfway down. Finally, to see if SLI support is enabled you need to look in the Xorg.0.log file and see if you have a line that reads;

Code:

(II) NVIDIA(0): NVIDIA SLI enabled.

After having said all of that, you should realize that glxgears is not an accurate test for determining 3d performance. Quoted from the nVidia documentation Chapter referenced previously;

Additionally from that same chapter it states that;

So after having done all of that, it still may not work, or may not work correctly. Lastly, it doesn't appear that Dragon Age runs under Linux, so I'm not sure how Linux SLI performance is going to help. You best bet would be to run the game under Windows directly, with the Windows drivers.

Good Luck..

 

I currently have it disabled and see the same 8X ...
I guess another re-install is nearby since there is no equivalent to CCleaner and it seems that I messed up my drivers again. Will try bypassing the Hardware Drivers and install through the Nvidia-installer next time...

 

Thank you the detailed answer!
I tried installing the drivers though the Hardware Drivers (recommended way) but as I said before, was getting 30% of the actual performance compared to the same cards/tests done by phoronix team.
Also after enabling the SLI (tried "Auto", "on" and "AFR" options) got a further reduced performance.
Then tried installing through envy and manually and the installation failed on all attempts.
I'll try now the manual install again following your guide and post the results - thanks again.

 

Ok, Here is an update.
I was able to do the manual install of the latest 195.30 drivers and get a serious boost in phoronix lightsmark test 1920X1200 rez with SLI enabled:
Single card - 137 FPS average
SLI On - 230 FPS average
However it's still way lower than what those cards can do in Linux:
According to this I should be hitting 300+ with a single and probably ~500-600 with SLI On...
Another thing is the choppy rendering in Compiz and any games, which disappears when SLI is Off.