low cpu an gpu usage with VR

Discussion in 'Technical & Support' started by Pablo11, Dec 8, 2018.

  1. Pablo11

    Pablo11 Registered

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    Hi
    I have noticed this lately when running new Sebring with Vr rift i am getting no more than 60 % usage with my GPU and around 35% usage with my Cpu.
    I also checked with my triples and the usage of my GPU go up to 99% and cpu up to 70% then no problem there.
    What is the problem with VR is that normal? I am experiencing some low performance with not only on this track.

    My system
    Aorus 1080ti
    i7 4790k
    DDr3 Kingston 1600
     
  2. Mknopfler

    Mknopfler Registered

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    I have the same problem with VR, it also happens with other simulators. From what I have read in different forums, the problem is that the CPU pre-render the frame before sending it to the GPU, this work is only done by a single core of the CPU, this is what limits the work of the GPU. Do not look at the total use, because that does not mean that all the cores works at 60%, it is possible that the core 0 is 90% and the rest at 10%.
     
  3. stonec

    stonec Registered

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    Pretty sure the reason you don't get 100% GPU usage is that VR locks to either 45 or 90 FPS. So there is usually some headroom left in the GPU to guarantee a steady 45/90 FPS, similar as in 2D when you use vsync. And yeah, the CPU use at 35% is normal because out of the 4 cores and 4 threads rF2 only uses a fraction.
     
  4. Pablo11

    Pablo11 Registered

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    I thought that when i disable asw and the fps drops below 90 my gpu should go 100% but it remains low 50% never more than 60 also cpu single core never more than 40%
     
    Last edited: Dec 9, 2018
  5. Pablo11

    Pablo11 Registered

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    I do not lok at total usage i have all my cores displayed on msi afterb . Im talking about single core usage
     
    Last edited: Dec 9, 2018

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