Any AMD users out there just wondering if anyone has tried re enabling SMT with dx12 since SU10 dropped? I’ve had it disabled quite a while after it seemed to help with smoothing things out a fair bit. Wonder how it runs now with it on 
Yes, I tried both with SU10. SMT off gave me better (smoother) results, but I need the PC to enter S3 which is not posssible without SMT. Anyway, the results are also good with SMT enabled. I leave it like that.
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I’ve been running with it off for a few weeks on my 5900x. I might try turning it back on for kicks.
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Well, before SU10 I used to have HT off(Intel) and it would give me a few more FPS compared to having it on.
But now with SU10 and DX12, I turned HT on and found that there is absolutely no change between on or off.
So I just left it on as it does perform better when you have multiple apps running.
I think you only get better performance with it off when using DX11.
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In dx12, I noticed that with smt off, I have about 4 cores totally pegged and then a couple more almost pegged and the remainder at >50%. When running the sim, task manager says the cpu is around 92% utilization.
With smt on, it was around 53% utilization and you can see alternating peaks on all cores. It’s passing the tasks between the threads. One goes up and the other goes down.
SMT off does seem a bit smoother in the sim.
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Me too. I fly in VR and I always had SMT off and the difference was noticeable. I took some measurements in SU10 during one of the beta’s and the results were virtually identical so now I run with SMT on. Note that I did all kinds of configurations comparing on vs off and they all show that with dx12 you can leave it on now. My dx11 results were not as consistent as the dx12 results. SMT off seemed to still make a slight improvement in dx11.
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I have SMT on now in my 5800X using DX12.
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I also noticed tht I gained about 4-5 extra fps by disabling HPET and also disabling Virtualization.
You might one to try that and see if it gains you anything as well
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Just tried on and off I’m getting a far better spread of cpu usage with SMT on in dx12 when it’s off CPU 1 is pretty much constantly 100% with SMT on load is spread out far better I’m seeing roughly 50% on cpu1 now
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I tried SMT on and off in the past, both on my Ryzen 2700X and my current 5950X. I never saw any performance difference between SMT on and off that I wouldn’t consider to be within margin of error. To me, it’s never made a difference either way.
Yes, I also saw the load better spread across my threads when SMT was on. When SMT was off though it still appeared that stuttering was minimized better. I have a 5900x so I still had 12 cores going with SMT off.
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Yeah either way it’s smoother but it was using the extra 8 virtual cores for something so I’ll see how it runs with the 16 so far so good 
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