prccowboy

I've used various profiles with success, but I'm currently using a slight derivative of BabyPapa1's suggestion above (only changing SLI compatibility bits DX10+DX11 and not forcing AFR2) I also made a few changes for personal taste (set FXAA on and Vsync to Fast) but these changes are really more for quality preferences rather than pure performance.

not necessarily, but it seems to impact some other bottleneck that was throttling my gpu's in Caucasus. After running more tests, I have much better SLI performance gains in other areas of the map but something about my first test conditions @ Sukhumi killed my SLI performance. on Nevada, SLI is a *BIG* game changer for me under all conditions (about 100% improvement). Also, don't you basically disable SLI performance when you use SLI AA?

Yes to Alt-Enter; clean and repair. After more experimentation I have realized that it is NOT an SLI issue - The SLI is working but something related to visible range is bottlenecking my overall performance in Caucasus (such that in most conditions the SLI is running below 50% utilization) If I drop the visible range setting (or change my view to limit the range) then I can get SLI gpu utilization up to 98% and I can see the SLI performance boost. (ex: Single gpu=60fps; SLI=100fps). I changed all other settings (texture level, tree visibility, etc.) and nothing else made a difference. Whatever is causing this performance bottleneck for my rig, it's only in 2.5OB Caucasus. I don't see it in Nevada or 1.5 Caucasus.

Thanks for the feedback BabyPapa. I took your message to mean that you use the default DCS:BS Nvidia profile and only change SLI compatibility DX10+DX11 bits to 0x081000F5 (Dirt 3, Dirt Rally). I just tried that and hit the best fps I've ever seen in Nevada (about 100% boost); however, I still don't see any change in Caucasus terrain - Given the low gpu utilization that I'm seeing on that terrain, something else must be bottlenecking on my rig with that map.

So, it's not just me then - not sure if that makes me feel better or worse. BTW, Nice screenshot

b00ce, what compatibility bits are you using? driver? I get a 75-90% boost in framerates with SLI on the Nevada map. I think that's worth consideration. This post is not a debate on whether SLI works in DCS, because it DOES (with profile tweaking). However, I would like to understand why it works with one terrain and not another for me.

Have you tried forcing SLI off and doing a comparison? My point is that I don't see any performance increase in Caucasus (in fact, performance drops) when using SLI. However, SLI does give me a boost in NTTR map

I thought the same, but it looks annoying. I also haven't seen this in anybody else's screenshots of 2.5 so I was wondering if it's just my setup.

With 2.5OB Caucasus, I am seeing a strange horizontal line (flat plane?) in the middle of the trees at medium distance. See attached photo. When I get closer and the detail increases, the trees look fine. Is it supposed to look like this?

Does anybody have SLI working in 2.5 with Caucasus? <=This was my original question edit (with latest findings): SLI does WORK in 2.5, but: Ultimately your performance is either limited by your CPU or GPU. Think of it as 2 guys running a race but tied together by a rope. If one is slow, he limits the speed of the other. In DCS, when the CPU gets maxed out then the gpu becomes underutilized and vice versa. Initially, I thought SLI wasn't working in 2.5 Caucasus because I was getting similar results with no sli (one gpu at 97% utilization) vs. SLI running (but both gpu's running below 50%). It turns out that one of my cpu cores was maxed so one videocard was enough to keep up with the cpu (and two cards was overkill). If I reduced cpu load but ran only one videocard then I still saw no improvement in fps (now my gpu was the bottleneck) However, I now have my cpu maxed and both gpu's running SLI at about 98% utilization and see a huge improvement in performance (now my cpu doesn't slow down my video cards and vice versa) I have written a guide to SLI setup (post #65) => HERE Everybody has a different rig and will have different bottlenecks, but the point of this post is to confirm SLI does work but performance will vary if you have something else bottlenecking your framerates.