High GPU usage after getting RTX

mmagdy88

New Member
Hello,

I've a bit of an issue here, I had GTX 1060 6GB and didn't have any issues with OBS, the GPU usage at all time wasn't going over 1% to 2%, now after getting RTX 2070 Super the GPU usage jumped up to 40% to 60%, this happened to my friend as well which he had GTX 1070 Ti without any issues but after upgrading to Super faced the same issue, what could cause that and how to fix it? Keep in mind that OBS is on the same settings, we just detached the old card and attached the new one then performed a clean installation of the new card's driver.

Rig specs:
  • MSI Z370 GAMING PLUS
  • Intel Core i7-8700
  • G.SKILL Ripjaws V 2x8GB DDR4 3200Mhz
  • MSI RTX 2070 Super GAMING TRIO
Log:

Note: I saw another post talking about reducing the number of sources and scenes, I did that and tried with 1 source and 1 scene but the same issue, when I switched to x264 rather than NVIDIA NVENC H.264 the issue disappeared.

Thanks in advance,
 

Attachments

  • Screenshot_2.png
    Screenshot_2.png
    11.7 KB · Views: 63
Last edited:

R1CH

Forum Admin
Developer
Are you doing a proper comparison by checking GPU frequencies? OBS may be using so little GPU that on your Super GPU it can run entirely in power saving mode, where your previous GPU was using full power.
 

mmagdy88

New Member
Good point, I've checked that now, the GPU Clock is sitting at 675Mhz while OBS is running, after closing it, its sitting on 300Mhz, GPU Memory clock with OBS is 810Mhz, without OBS is 405Mhz, GPU Video Clock with OBS is 570Mhz, without OBS is 540 Mhz.
 

carlmmii

Active Member
The core clock when running at full power state is 1605mhz, so your GPU isn't seeing the need to ramp up to full power levels. That's why you're seeing "more usage", but what it's actually showing is the comparison to the lower maximum, because it's not at that higher power state. It is a slightly higher power state than idle, but it's not actually seeing the need to power up fully.

If you're not having any performance issues, then this is working as intended.

Also, you should use the Performance tab to check GPU usage. That gives the breakdown of what's actually being used on the GPU. The percentage shown on the Processes tab is only useful in a general sense for if you're doing normal 2d/3d rendering workloads... scene compositing and encoding are not the normal use case, and the usage percentages only make sense when seeing the individual reported usages for each subsystem.
 

koala

Active Member
There isn't anything broken. It's working correctly.
What happens is this: OBS needs a fixed amount of computing resources on your GPU as soon as it is started. Let's assume it is 5% of the GPU capability.
A GPU has 2 modes of operation: one powersaving with reduced computing power and one full power.
The reduced power reduces the computing capability to about 5% of full power mode. This is still enough to display the Windows desktop if there isn't anything else using the GPU.
With your old GPU, as soon as you started OBS, the computing demand of OBS plus Windows desktop is higher than the power saving computing power of the GPU, so it switches to full power and OBS is using 5% of this, just as you observed.

With your new GPU something different happens. The new GPU is so powerful, it is even in powersaving mode powerful enough to support OBS and the Windows desktop, so it stays in powersaving mode. The OBS computing demand is a substantial amount of the powersaving resources, which is visualized as 50% GPU usage. To see the switch from powersaving to full power mode, start some game. You will see OBS suddenly drops to 5% or less. OBS still needs the same amount of resources in absolute values, but since the new GPU is 100 times more powerful in full power mode, this absolute value is now negligible.

To see actual GPU power saving mode, power consumption and more, try gpu-z.
 

mmagdy88

New Member
The core clock when running at full power state is 1605mhz, so your GPU isn't seeing the need to ramp up to full power levels. That's why you're seeing "more usage", but what it's actually showing is the comparison to the lower maximum, because it's not at that higher power state. It is a slightly higher power state than idle, but it's not actually seeing the need to power up fully.

If you're not having any performance issues, then this is working as intended.

Also, you should use the Performance tab to check GPU usage. That gives the breakdown of what's actually being used on the GPU. The percentage shown on the Processes tab is only useful in a general sense for if you're doing normal 2d/3d rendering workloads... scene compositing and encoding are not the normal use case, and the usage percentages only make sense when seeing the individual reported usages for each subsystem.

I got you screenshots from Performance tab with and without OBS.

With OBS:
With.png

Without OBS:
Without.png

There isn't anything broken. It's working correctly.
What happens is this: OBS needs a fixed amount of computing resources on your GPU as soon as it is started. Let's assume it is 5% of the GPU capability.
A GPU has 2 modes of operation: one powersaving with reduced computing power and one full power.
The reduced power reduces the computing capability to about 5% of full power mode. This is still enough to display the Windows desktop if there isn't anything else using the GPU.
With your old GPU, as soon as you started OBS, the computing demand of OBS plus Windows desktop is higher than the power saving computing power of the GPU, so it switches to full power and OBS is using 5% of this, just as you observed.

With your new GPU something different happens. The new GPU is so powerful, it is even in powersaving mode powerful enough to support OBS and the Windows desktop, so it stays in powersaving mode. The OBS computing demand is a substantial amount of the powersaving resources, which is visualized as 50% GPU usage. To see the switch from powersaving to full power mode, start some game. You will see OBS suddenly drops to 5% or less. OBS still needs the same amount of resources in absolute values, but since the new GPU is 100 times more powerful in full power mode, this absolute value is now negligible.

To see actual GPU power saving mode, power consumption and more, try gpu-z.

That makes sense, I've added 2 screenshots for you with OBS and without OBS using GPU-Z

With OBS:
With 1.png

Without OBS:
Without 1.png

What do you think?

Thanks both for your reply.
 

R1CH

Forum Admin
Developer
Looks totally fine, in the last screenshot you can see your GPU is limiting performance (PerfCap reason) because it is "idle". It can easily handle the load of OBS without increasing the clock speed, so it does so in order to save power. As soon as more performance is needed, the clock speeds will jump up and the percentage use from OBS will decrease accordingly.
 

mmagdy88

New Member
Looks totally fine, in the last screenshot you can see your GPU is limiting performance (PerfCap reason) because it is "idle". It can easily handle the load of OBS without increasing the clock speed, so it does so in order to save power. As soon as more performance is needed, the clock speeds will jump up and the percentage use from OBS will decrease accordingly.

Thanks for your help, really appreciate it.
 
Top