I am running BOINC in Windows 7/64-bit on a core i5-760 desktop PC. I just started playing with BOINC and I have a general question:

On a multi-core system like the i5, is it preferable to limit BOINC based on the number of cores or overall CPU usage?

Which results in more effective CPU utilization? Which is recommended for running BOINC while the system is in use and minimizing lag? Which is better for limiting thermal abuse of the CPU (with a stock cooler)?

I'm also curious if the same recommendations would hold for a multiple-core system with hyperthreading, like an Atom 510.

I started wondering about this after I noticed that 100% processors and 50% CPU time limit causes the system load and core temperatures to flip-flop every second. In contrast, 50% processors and 100% CPU seemed to give more consistent system load and temps. Both options didn't seem to significantly slow down the system, but I don't really have an objective way to quantify system responsiveness.

Thanks for the reply. I'll check out the process management apps you mentioned.

It might be helpful to have separate CPU limit settings for when the machine is in use vs. idle. That way I could tell BOINC to use 2/4 cores when I'm using the PC, and 4/4+GPU when the machine is idle. Then again, 2/4 cores at 100% CPU limit and 4/4 cores at 50% (due to thermal concerns) might yield the same throughput - not sure about that though.

Another question - is it possible to tell if BOINC is actually using my GPU for calculation when my PC is idle? I know it detects the GPU and it is supported (I see a line about CUDA in the message log) but I don't see any more messages about actually utilizing GPU when the machine is idle. Do only some applications make use of the GPU?

Thanks.

Suggestion for extra setting: separate screen saver from background modus.

It would be handy to separate the settings for running in the background (when one is using his computer) and in screensaver mode. In the latter you typically don't mind your computer (laptop in my case) to use 100% CPU. But in background mode you would want to limit the CPU use to avoid fan noise.

Currently as a laptop user I have to choose between either running in the background whole the time at low CPU or only running screensaver at 100%. A nice combo could mean I can calculate at least double or triple the amount of work per 24h