Is it possible to configure BOINC to compute on a specific GPU always, but only use the CPU when idle? Currently, I have my computing settings set to "suspend when computer is in use" which applies to all processors. I see an option to "Suspend GPU computing when in use", but I'm looking for an option to just suspend the CPU. I have a spare GPU in my PC that I'm not using.

The developers have always treated this in a very literal-minded way: if you compute on a GPU, there is always some CPU activity required, so in their view it is impossible to pause the CPU while still running a GPU.

I think the rest of us have a more relaxed view of the capabilities of a modern multi-tasking operating system. The machine I'm typing this on is running a GPU task with <2% (of one CPU core out of four) required to provide the GPU support. That <2% is a 30-second average, and most of the time the CPU usage is lower than many Windows background processes.

GPU applications vary in the amount of CPU support they require - depending on the project (computational complexity), development tools, driver sophistication, and programmer concerned. But I agree with you - the ability to manage resource usage in this way should be provided for users to activate, or not, as they choose. But don't hold your breath waiting for the developers to change their minds: it's been requested many times before, and rejected every time.

If you search the forums, you'll find examples how you can configure cc_config.xml and app_config.xml to use a specific GPGPU down to the single science app exact. Not sure if you can GPU compute when the CPU is set to only compute when idle because GPU jobs are usually dependent on whole or part of a CPU core to control the GPU job.

First try the activity menu to "run based on preferences" and tick box in computing preferences to "suspend when computer is in use" and untick the "suspend GPU computing when computer is in use" to see if the GPU continues.

Edit: Slow typing I did.

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Coelum Non Animum Mutant, Qui Trans Mare Currunt

OK. That makes sense. I tried adjusting the preferences as you suggested, but no luck. I think I'll experiment with leaving the CPU time to some low setting, say 5%.

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