MGPU Questions

With the ability to now use GPU's from both AMD and nVidia together, has anyone (devs included) done any testing with Cross Vendor GPU's of differing performance tiers? I currently own a 980Ti (Should have bought that Fury X instead...) But I have acouple of R9 280X cards from my last build that are just collecting dust. I've pondered slapping one into my computer to pair up with the 980Ti just to see what I would get from it. I'm sure it's not ideal, but how is scaling with such a mis matched couple? Is MGPU in Ashes done in such a way that I'll never get more than double the frame rate of the slowest card or is the processing load balanced in such a way that the slower card compliment some of the...shortcomings... of the 980Ti?

 

If the Devs havn't played with this much I'd be happy to pull out my "For Science" hat.

9,956 views 7 replies
Reply #1 Top

I don't know for sure but I think that Ashes supports only 2 cards atm. I would also expect to see perfomance improvements with 980ti+280x but I may be totally wrong.

One thing I know for sure is that with AMD FX CPU I have absolutely no gain using 2xR9 290s over one.

Maybe AMD cpus are just bad running this game or there is somekind of work to be done in that front.

Reply #2 Top

Quoting Waza88, reply 1

Maybe AMD cpus are just bad running this game or there is somekind of work to be done in that front.

AMD CPU's are 2+ years old with old Tech, you need to wait for Zen CPU's........ till September.....

Reply #3 Top

I found the issue. For some reason steam FPS counter caused bad performance. I got nice 50% boost with dual GPU ofthe disabling it.

Thats not to say that my FX 8350 performs great. I'm still stuck 45FPSish regardless of graphics quality.

Reply #4 Top

Quoting Waza88, reply 3

I found the issue. For some reason steam FPS counter caused bad performance. I got nice 50% boost with dual GPU ofthe disabling it.

Thats not to say that my FX 8350 performs great. I'm still stuck 45FPSish regardless of graphics quality.

 

Take out the crossfire Bridge between your cards and disable Crossfire in the drivers then enable MGPU in the game. I've been told this helps. Sounds odd right? Try it.

 

EDIT: Here is a benchmark from an AMD user...AMD CPU AMD GPU

https://app.box.com/s/6pwx64gyehw1utjgivcz80ab1t82h1pg

 

AMD's CPU's are perfectly find for Ashes, in fact AMD CPU's have been better at highly threaded workloads than Intel CPU's (There are exceptions). The IPC per core is lower, but with the threading Ashes uses in DX12 AMD does well enough.

Reply #5 Top

Quoting philldoe70555, reply 4

AMD's CPU's are perfectly find for Ashes, in fact AMD CPU's have been better at highly threaded workloads than Intel CPU's (There are exceptions). The IPC per core is lower, but with the threading Ashes uses in DX12 AMD does well enough.

 

Well my FX 8350 is now clocked at 4950MHz and I am stuck with 45FPS 1440p.  I can change the graphics preset from low to crazy 8x MSAA and get pretty much same result. CPU usage is around 60-80% with dual GPU. 

If I switch to single CPU my framerate on low settings go up to 60 FPS.

Perhaps there are further issues somewhere.


== Hardware Configuration ================================================
GPU 0:        AMD Radeon R9 200 Series
GPU 1:        AMD Radeon R9 200 Series
CPU:        AuthenticAMD
        AMD FX(tm)-8350 Eight-Core Processor           
Physical Cores:            4
Logical Cores:            8
Physical Memory:         16296 MB
Allocatable Memory:        134217727 MB
==========================================================================


== Configuration =========================================================
API:                        DirectX 12
==========================================================================
Quality Preset:                    Custom
==========================================================================

Resolution:                2560x1440
Fullscreen:                True
Bloom Quality:                High
PointLight Quality:            High
Glare Quality:                High
Shading Samples:             16 million
Terrain Shading Samples:         16 million
Shadow Quality:                High
Temporal AA Duration:            0
Temporal AA Time Slice:            0
Multisample Anti-Aliasing:        8x
Texture Rank :                1


== Total Avg Results =================================================
Total Time:                     60.000816 ms per frame
Avg Framerate:                     45.264767 FPS (22.092237 ms)
Weighted Framerate:                 44.891548 FPS (22.275908 ms)
CPU frame rate (estimated if not GPU bound):     45.840366 FPS (21.814835 ms)
Percent GPU Bound:                 0.000000 %
Driver throughput (Batches per ms):         2025.056274 Batches
Average Batches per frame:             17793.558594 Batches
==========================================================================

 

########################################################################################

VS LOW PRESET

########################################################################################


== Hardware Configuration ================================================
GPU 0:        AMD Radeon R9 200 Series
GPU 1:        AMD Radeon R9 200 Series
CPU:        AuthenticAMD
        AMD FX(tm)-8350 Eight-Core Processor           
Physical Cores:            4
Logical Cores:            8
Physical Memory:         16296 MB
Allocatable Memory:        134217727 MB
==========================================================================


== Configuration =========================================================
API:                        DirectX 12
==========================================================================
Quality Preset:                    Low
==========================================================================

Resolution:                2560x1440
Fullscreen:                True
Bloom Quality:                High
PointLight Quality:            Off
Glare Quality:                Off
Shading Samples:             4 million
Terrain Shading Samples:         4 million
Shadow Quality:                Off
Temporal AA Duration:            0
Temporal AA Time Slice:            0
Multisample Anti-Aliasing:        1x
Texture Rank :                2


== Total Avg Results =================================================
Total Time:                     60.006741 ms per frame
Avg Framerate:                     48.948463 FPS (20.429651 ms)
Weighted Framerate:                 48.602123 FPS (20.575233 ms)
CPU frame rate (estimated if not GPU bound):     48.487041 FPS (20.624067 ms)
Percent GPU Bound:                 0.000000 %
Driver throughput (Batches per ms):         973.569397 Batches
Average Batches per frame:             8345.570313 Batches
==========================================================================

Reply #6 Top

Your frame rate at 1440p is slightly better than my rig at 1080p and I have a 2500k @ 4.8Ghz. I've heard mention that turning off the steam FPS counter and overlay helps in certain situations. You may want to look into that.

 

EDIT: Any chance I can get an answer from a dev about my original question?

Reply #7 Top

As noted above, only 2 GPUs are current supported in mGPU mode. There have been a number of articles published recently which test mGPU with various cards of different manufacturer and capabilities. You can see one example here and more in the News section on the forum. We have also tested various configurations.

Improving the performance of disparate GPUs is a long term goal. It makes a lot of sense since most desktops use a dGPU and leave the low-performance iGPU sitting idle. The team isn't ready to tackle this just yet however.