I will be getting my second GTX 470 in a day or two, but I'm aware that this engine is unstable with crossfire and SLi, anyone managed a stable setup? I have Nvidia inspector installed.

My setup will consist...

AMD AM3 Phenom II x4 quad core 3ghz
16gig 1600mhz system ram
and of course a pair of GTX 470's

Any tips welcome, thanks for reading.

I have a GTX590, which is 2 cards in one and is SLI just the same...no instability at all, but I do suffer from micro-stutters (not unusual for SLIs) when I really push it with tonnes of texture and shader mods...nothing that can't be fixed through vsync + fps limiter though. Suggestions:

- test 1st person microstutters by going indoors and moving mouse around carpets and furniture
- (in case you haven't) update to latest nvidia Beta driver...performs best for Skyrim

Use the 290.53 beta driver, that's really all there is to it. Its got a Skyrim profile and that profile works quite nicely.

Skyrim unstable with SLI? Not in my end of town, and AMD may have had texture problems but they received a driver fix for that.
You can keep NVIDIA Inspector in harbor, it is not needed because of what BumpInThe Night will tell you.

Yep, and that is why NVIDIA SLI is just fine and you don't need inspector.
Now launch your two cards and get ready to enjoy better fps, the game is awesome.
Enjoy

I've got 2x GTX 470's as well and I can offer a couple of things that worked for me.

1) If you are not getting the performance you expect, set the AA & AF in the Skyrim Launcher to off, set everything else in the launcher to max. Then tweak you AA & AF within the Skyrim profile in the nvidia Control Panel. I was very disappointed with my performance, but this one change made all the difference in the world. Now, (according to Fraps) I'm running a very steady 60 FPS and it's buttery smooth. Only in cities do I really see a drop in FPS, but that's only to around 45 to 50 give or take. Even then, it's butter!

2) This may sound obvious, but be sure and check in the CP to make sure SLI is in fact enabled. For some stupid reason that no one has been able to help me with, when I boot up and check the CP my SLI is not enabled. So I have to re-boot everytime I start my rig to get the SLI to enable - even though it was enabled when I shut down the night before or whenever. (It's very annoying.)

3) After you get it all up and running, I suggest some of the Hi-Res texture replacers like Skyrim HD and the Floura overhaul. I also love Realistic Colors and Real Nights v15 with HDR. The vanilla game is already stunning, but these mods really make it unbelievable. Here's some links:

http://www.skyrimnexus.com/downloads/file.php?id=1875 - Realistic Colors and Real Nights v15 with HDR

http://www.skyrimnexus.com/downloads/file.php?id=2146 - Serious HD Retexture Landscape Skyrim

http://www.skyrimnexus.com/downloads/file.php?id=141 - Skyrim Flora Overhaul

http://www.skyrimnexus.com/downloads/file.php?id=607 - Skyrim HD - 2K Textures

@ Balok - have you been able to get Inspector or Nvidia Control Panel to force ANY AA when in-game AA is shut off completely? I have had to set minimum (2x) AA in-game in order to be able to get any nvidia AA goodies to kick in

there are 3 settings for "AA Mode"...

Application control (nvidia does nothing)
Override any application setting (Nvidia has complete control)<<Enhance the Application settings ( game and Nvidia work together)

Im running 2x gtx 580s and sli seems to run fine in for me with latest drivers of course. Its just such a CPU hog that it doesnt really take advantage. my gpus never get over 60% usage, usually 40% at the most when outside yet I get frame drops to about 45-50 when looking at cities even with an i7 2600k @ 4.2ghz!. luckily the Skyboost mod helps out, still annoying tho

I will try some of your control panel tips Balok does it force the gpu to work harder?

Ya, from day 1 with Skryim, I've fiddled with these settings and not once have I ever got "override" to work...no value in the AA section of Inspection has ever applied to the game, unless in-game I apply the x2 minimum THEN 'enhance' in Inspector...then all my values work.

This has been discussed before...you would be the first I've ever seen get over-ride to work. Have you done specific screenie tests for this? Turn in-game AA to off, then see if you can get any nvidia AA to stick?

Maybe with crossfire. Not with SLI.

I'm running with three 580's in SLI and a 460 for dedicated physx.

The only problem I have had that can be atributed to the SLI is one where the surfice of water flashes rapidly. Its very bothersome but I belive its caused by a high frame rate, which in my instance is provided by the SLI setup. Apart from that no issues caused by SLI what so ever.

I should add I am running the 290.36 driver. That might or might not make a differance.

I have a Crossfire setup (two 5850 cards) and can report that the game is stable with those. Selected Ultra settings in the options. No issues and smooth as a baby's bottom.

I am not alone! Yah I get that reflection flicker too but I've found its very much attributed to how many reflection types I've got turned on, 3/4 (objs, land & sky but not trees) and I'm okay but if I've got all four on its pretty much an always present thing and especially out in some very watery areas like say that coastline east of Windhelm. Believe me high FPS isn't the source either, I run at a resolution and with enough mods that I'll dip even into the 20s while wandering the wilderness and the reflection flicker is present regardless.

So yah turn off the trees reflection and see how it goes, worked for me.