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Old 2011-06-18, 17:14   #1
Chuck
 
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May 2011
Orange Park, FL

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Default Don't understand this mfaktc behavior

I don't understand why this is happening: I am running v0.17-Win 64 bit mfaktc. SievePrimesAdjust is set to 1 and always quickly adjusts itself to 5000. I am factoring in the range M57000000. The average rate stays nearly constant at 168M/s and the wait time is around 135us.

I am using a GTX 580 and the GPU usage is a constant 41% (mfaktc is the only significant GPU user). mfaktc is using 17% CPU (Core-i7 970 six-core hyperthreading off).

Prime95 is also running using the remainder of the CPU capacity. If I stop Prime95, the mfaktc throughput DROPS to 102M/s and the wait time drops to 85us. The GPU usage falls to 25%.

How is it possible that mfaktc is performing better when there is a heavy Prime95 load on the system?
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Old 2011-06-18, 17:18   #2
TheJudger
 
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"Oliver"
Mar 2005
Germany

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Please check whether the CPU downclocks (EIST aka Speedstep) when only mfaktc is running or not.

Oliver
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Old 2011-06-18, 17:24   #3
Chuck
 
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OK that's it — downclocked from 3570 MHz to 2040 MHz when I stopped Prime95. Thanks
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