So what is the current status of SLI for P3D v3.2?

[Noel 4,487]

I guess DirectX 12 has not been or can't be implemented for P3D yet and I wonder what SLI would bring for me.  I aim to have the sim setup so that it is CPU limited always, which is to say sliders affecting GPU utilization I have dialed back enough to keep GPU utilization around 90% +/- depending on the exact scenario and moment in time.  Since I'm not seeing much difference in what those slider do it seems like SLI won't add much, but again that is based on the logic above.

[westman 257]

Hi Noel

Did a test with P3D V3.2

The problem is that for example a 980ti is very strong you havent ben gpu bound , example approx 5ghz on a 6700k you ar close to the gpu bound point .

What a see is that P3D have Done a good job SLI work as good as it can approx 70% gain.

The only way to detrimite if it works is to have a really strong CPU and gpu in SLI thats is not as strong as a 980Ti you need to be gpu bound in SLI .

What a did was downclock and Overclocked the 6700k from 1.8ghz to 5ghz used a Old Gtx 690.

Start was 1.8ghz a get the single gpu core CPU bound then when reaced 2.5 ghz a get gpu bound ,

The frames raised from 19fps to 25 at 2.5ghz and have the same at 5ghz.

Enabled SLI started from 1.8ghz losed 1fps at 2.6ghz a get 26fps and stoppad to raise at 4.6ghz at 43fps and have that to 5ghz.

 

Conclusin is that SLI works but we have no CPU with enough power take benefit of the 980Ti in SLI

2 X 970 and a 4.8ghz 6700k with 3400mhz + mems gone work.

 

One more thing the minimum gpu for Skylake 6700k at 4.5-4.6 ghz if you want the sliders to the right is a Gtx 970 or higher, with the 970 you get gpu bound at approx 4.7ghz

 

Test was FSXMark11 files modded for P3D , with settings as The video from Matt or Robs settings monitor 1920x1080.

[hovercrafter 10]

Very informative, thank you Westman.

 

Gordon

[Bob Scott 7,716]

CPU throughput isn't the only factor in consideration. With a 4.6GHz 4790K I can bring two 980Ti cards in SLI to their knees with P3D, heavy clouds, 4xSGSS antialiasing and a 4K display...you can load the GPU(s) to their limit without saturating the PCIE bus with certain AA modes and high display resolutions (4K or multi-monitor).

With a single 980Ti, P3D will start to stutter in places where two in SLI still keeps things smooth, especially with HD panels in heavy wx with rain and/or volumetric fog. Once GPU ute rates hit the 90% mark, stuttering sets in. I look for 60% in clear wx and without SGSS that generally gives me enough headroom to hit weather without stutters or dropping below my locked 30fps framerate. On a 1920x1080 monitor I could probably get away with a single card, but I wouldn't think about trying that with a large (55") 4K monitor where even minor stutters or jaggies prove very distracting.

Regards

[westman 257]

Bob

Thats true it was the same in FSX no problem with scenarios you describe.

My eng is bad not sure it was clear what a mean.

The diff to fsx is that SLI realy works in P3D not broken.

My 2 cents is that P3D works even in quad SLI.

A single 1920x1080 monitor with 970 is minimum your right the 980ti is optimal for that , then with multi monitor 4k setups Its another ballgame , my suggestions was for mainstream user.

 

I have run multimonitor setups a long time , starting with fs2004 with WideView and 5pc setup.

Run my prosim 737 Boeing sim with multimonitor setup , shall start a q400 projekt with SLI hoppfully with upcoming gtx 1080 in SLI

 

Remember the discussing here with the first Titan when testing that with Dazz cloudtest....

The 580 to 680 discussion.

 

Really a want to proof that SLI works 100% in P3D

We need booth CPU and Gpu power and Its on the way.

 

Regards / Hasse

[gboz 157]

 

 

We need booth CPU and Gpu power and Its on the way.

 

I guess Pascal is one, what is the other?

 

gb.

[Noel 4,487]

Thanks all for this info