Does TwinView work with Nvidia SLI?

Question

This might be a rubbish question for AskUbuntu but I'm getting a hardware itch and I think the cheapest way to alleviate it is by chucking another Nvidia GTX 260 in my box and strapping it to my existing one...

But I use Twinview (that is two monitors coming out my one card) showing a single screen. I also use Compiz and I also play games, and watch video using VDPAU.

So before I spend £100 on another card, I'd like to know what I'm getting myself in for. Does twinview work with SLI? Does 3D performance increase as much as it does in Windows? Where's Wally? Should I just forget it for now and buy a mid-range 5xx in a year or so?

Answer 1

I think this is for the Windows driver set, but I hope it can be used also to configure Linux TwinView with SLI: http://www.slizone.com/object/sli_multi_monitor.html

Answer 2

I realise that it is too late to provide a useful answer to your question but I will post this anyway, for future googlers to find:

SLI is NOT compatible with twinview. It says so in nvidia's driver documentation. There are two alternative options though:

1) Set up each screen as a separate xscreen - the disadvantage being that you won't be able to drag windows from one screen to the other. The nvidia control panel can be used to set this up.

2) Use a utility to convince the xserver that your two smaller screens are, in fact, one big one. This will cause applications to not full screen correctly, however. I'm afraid I don't know what this utility is called.

Answer 3

It should work

NVidia's Linux drivers are generally quite good. Their hardware is used in high-performance-computing a lot, which is why Linux support (now) is rather excellent. Of course you may even see decreased performance on some applications. But this isn't exclusive to Linux. Just game developers on Windows doing a good job of optimising for SLI.

Maybe somebody who knows a bit more about hardware could advise you whether the GTS 450 mightn't be a better deal. (Don't laugh at me if that's ridiculous...)

Answer 4

Well I found this post: http://www.nvnews.net/vbulletin/showthread.php?t=153283

And the people there are somewhat less than happy with SLI performance on Linux. Some of the posts are quite recent and there's no sign of performance being any better than single-card mode.

I guess I'll keep my eye on the driver releases to see if nvidia improve things.