Hello,

I have switched my card from low-end geforce bought around 2,5 years ago to PNY Quadro M4000 and to my surprise the difference in performance was not so big.

I decided to check my computer on GPU-Z software while running simulations and rendering. It shows that GPU Core Clock jumps from 135 MHz (when idle) to 772 MHz but what is interesting GPU Load stays extremely low - that is below 3%!! Does it mean that my processor (Intel i7) is calculating almost everything?

When I test computer on 3DMark GPU Load goes to 100%.

Can anyone explain to me what is going on? I would be very grateful if you could try GPU-Z and let me know what are your results.

What simulation type were testing with?
For FLIP you have to manually enable OpenCL on the solver, it is off by default. Even when it is enabled I only get about a 30% usage out of my graphics card.

In Houdini you want a good graphics card so you get an accurate robust viewport display. Also for 3rd party GPU render systems like Redshift or Octane. You may also see some GPU usage if you viewport render using MPlay.

I run fluids simulation. I turned on “Use OpenCL” in solver (thanks for this information) and now my GPU Load is higher but still very low - around 8-10%.

I have also very long render times of simple things such as default grey grid - 3000x3000 in PBR it takes around 30 seconds for others and for me it's 1 minute (2 min 40 seconds if I don't turn off preview).

I thought that render time depends on graphics card but during rendering I have 2% GPU load. Is it normal?

Mantra is a CPU renderer - your GPU has nothing to do with it.

OMG So that's why I didn't see much difference I always thought that it's graphic card that is responsible for everything regarding simulations and rendering.

If you are running Houdini Indie license or better you have the option of using a 3rd party render system. The Redshift GPU render system will make use of your video card and greatly decrease your render time. Redshift offers a free demo version so you can try it out. This option is not available to users of the Houdini apprentice software version.