Not sure where to put this, move it if you so choose.

Based on my recent experience, I think that there needs to be a reassessment of the recommended CPU usage setting with the various new processors.

My understanding has been that the best setting on laptops was CPU usage at 60%, and that was set as a default in BOINC. My understanding was that, the user could run a desktop at CPU usage at 100%.

What I found, using the Coretemp software tool, was that in all cases, these settings resulted in my processors running very near to their maximum allowable temperatures. I have in desktops an i7-920, and an i7-3930K. In my laptops, I havean i5-520M, an i7-840Q, and an i7-2720QM. Nothing is overclocked; all use Intel's "Turbo".

I cut back the CPU usage in the desktops to 60% and in the laptops to 50%. The result was that they are all now running about 20degC lower than their maximums.

I cannot find any settings in BOINC Manager to affect the GPU's two Nvidia GTX580's, in my newest machine. The temperature gauge for them shows them to be low enough to not be a problem.

I would welcome a discussion of this issue.

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Gee Whiz, the silence is deafening.

I raised the same issue in the WCG forums because I find some very bright people there. I got a lot of discussion. Not w3hat I wanted, but definitely people with ideas.

But, hey, this is the mother ship.

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Not sure where to put this, move it if you so choose.

Based on my recent experience, I think that there needs to be a reassessment of the recommended CPU usage setting with the various new processors.

My understanding has been that the best setting on laptops was CPU usage at 60%, and that was set as a default in BOINC. My understanding was that, the user could run a desktop at CPU usage at 100%.

What I found, using the Coretemp software tool, was that in all cases, these settings resulted in my processors running very near to their maximum allowable temperatures. I have in desktops an i7-920, and an i7-3930K. In my laptops, I havean i5-520M, an i7-840Q, and an i7-2720QM. Nothing is overclocked; all use Intel's "Turbo".

I cut back the CPU usage in the desktops to 60% and in the laptops to 50%. The result was that they are all now running about 20degC lower than their maximums.

I cannot find any settings in BOINC Manager to affect the GPU's two Nvidia GTX580's, in my newest machine. The temperature gauge for them shows them to be low enough to not be a problem.

I would welcome a discussion of this issue.

What type of heatsinks are you using on your CPUs? The i7-920 runs hot because of the 130 watt TPD. If you're using the stock heatsinks running @ 100% is a very bad idea. I have no experience with the 3930K but I would not run that @ 100% with the stock heatsink either. I do have several 2600k CPUs that are air cooled with aftermarket coolers and they run 24/7 without issues. AFAIK there are no settings in BOINC to adjust the GPU settings. For that you'll need a third party tool like MSI afterburner.

nanoprobe-

Grateful for your remarks, you dropped the other shoe on the i7-920. I am running it at 60% usage, all cores. Everything is fine. The heat sinks are whatever is standard.

The i7-3930K has a sealed liquid cooler. That machine is set for ten threads at 100% CPU time. That is a huge rig, with twin GTX 580's also with sealed liquid cooling.

Whatever the reason, this machine runs better temp wise with less cores and running at 100%; all my other machines run best with all cores, but at 50-60% depending.

Again, thanks for the remarks.

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Just a guess but if you're running hot with sealed liquid cooling then you could have an air flow problem with your case. For a test pull the side cover off of your case and let it run for a while. If the temps drop significantly(10c or more) then air flow is your problem.
As for the i7-920, 60% load is probably all you can hope for with the stock heatsink. One thing you can try is turning off HT. That will probably drop your temps at least 10c. Then you can raise the 60% usage higher and probably see little drop in overall performance because 8 threads with HT on is only 20-25% faster than 4 threads w/o HT and you'll put much less strain on the CPU.

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nanoprobe-

Thanks. The i7-3930k did in fact have an airflow problem, not the case itself, just my own stupidity, since corrected. The case, specially designed for heat, by Maingear, actually has everything inside rotated up 90 degrees, e.g., all of the cabling attaches to ports on the top, not the back, and all the heat flows up and out through generous grills. But I had the thing under a desk, with only about 3" of clearance on top. So, the heat had no where to go. User error, the cause of most problems.

The machine could not be moved; but the desk I had room to move well away from the case. So, now, running 10 threads at 100% usage, and two threads held out to accommodate the GPU's, the temps are generally from 63-68deg C, with a limit on the CPU from Intel of 91 deg C. Two days ago, this unit did about 200,000 credits, at about 65 deg C average.

I will definitely look at the suggestions for the i7-920.

Thanks again.

But, again, I still think there is an issue to be addressed for all users with these fancy new processors. I think that BOINC still installs with a default of 60% usage, and i think many desktop users will up that to 100% almost immediately, leaving the 60% for laptops.

I think people need to get a temperature gauge - I use CoreTemp - and keep it loaded and minimized. And, pay attention to it.

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