How to get multiple video cards engaged in a render.

JMatteson

I have a large desktop machine with a pair of Nvidia 970 cards installed. The cards are bridged. According to the device manager, both cards are on the same revision driver.

I have a bear of a render to work on. It is multiple hours and pretty much locks the machine up with 98/99% CPU utilization. What is suprising is that the video cards are not being touched. 1% on one and the other is at 0% (according to the resource monitor). Where do I go to ensure that DAZ 4.10Pro knows that there are two cards installed, and both are availble for its use?

 

Thanks.

fastbike1

Two things to consider:

1) Nvidia does not recommend using SLI with Iray

2) If your Scene requires more Vram than an Nvidia GPU has available, that GPU will be dropped from the render. Any other Nvidia GPUs with sufficent VRAM will content to be used in the render. Your post suggests that the scene requires more Vram than the GTX 970 has (4GB). Otherwise the CPU utilization will drop after the GPU Vram is loaded. Vram of multiple cards is NOT summed for Iray.

See attached for locating/specifyong video cards. One final tip: do not select GPU + CPU. this will tie up your machine and will not result in an appreciably faster render. If the render needs to drop to CPU, this will happen automatically.

ebergerly

Yeah, what fastbike1 said...

BTW, what are you looking at to see if the GPU's are being utilized? What "resource monitor"?

If it's the GPU monitors in W10 Task Manager, keep in mind they don't necessarily default to show you the busy render engine. It may look like the GPU's are dead, but in fact you're just not seeing the appropriate info.