I just noticed the following: 2 machines have the same CPU, yet have 20% difference on the BOINC CPU benchmarks:

Computer 7158111 (other machine)

Intel(R) Core(TM) i7-4770K CPU @ 3.50GHz [Family 6 Model 60 Stepping 3]

Measured floating point speed 4820.23 million ops/sec
Measured integer speed 17988.95 million ops/sec


Computer 7138752 (my machine)

Intel(R) Core(TM) i7-4770K CPU @ 3.50GHz [Family 6 Model 60 Stepping 3]

Measured floating point speed 4005.99 million ops/sec
Measured integer speed 15098.11 million ops/sec

About a 20% difference!!!

Any idea why? These are CPU benchmarks, remember, and so graphics cards should have no effect on them. Maybe RAM speed might be different, but these CPUs have a lot of cache, so system RAM shouldn't affect them much, I would think (depending on how the benchmarks are coded, of course).

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Any chance there are cooling/temperature differences between the two machines ? [ also could he be overclocked ? 20% seems achievable with those ]

You can monitor the clocks with CPU-Z or similar to see if the rate is dropping either due to temperatures or other power setting.

Also, assuming Windows 7 (not sure where in 8.1 etc), in the OS advanced power settings there is an entry for the minimum CPU power state. For dedicated crunching, gaming etc, where the cooling and power are sufficient I set that minimum to 100%.

Side note: It does seem to have an effect on feeding the GPU more promptly if the CPU is awake (logically), which is via the DPC (software interrupt) mechanims. There can be noticeable DPC latency spikes feeding the GPU of the CPU is clocked down.

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"Living by the wisdom of computer science doesn't sound so bad after all. And unlike most advice, it's backed up by proofs." -- Algorithms to live by: The computer science of human decisions.

The 2 computers you have on the seti list are NOT the same. So expect different results.

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My benchmarks dropped considerably after upgrading BOINC 7.4.36 > 7.4.42

Keifer

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Do you have other things running?

Do you have other things running?

Nope, it is a dedicated cruncher.

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The 2 computers you have on the seti list are NOT the same. So expect different results.

I know that, but the difference strikes me as too large for just that. Unless the benchmark forces use of RAM, I can't see where that would make a significant difference. But then they wouldn't be good CPU benchmarks.

Same CPU and likely same Intel chipsets, right?

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Another one has 8 processors, maybe it has HT enabled?

The 2 computers you have on the seti list are NOT the same. So expect different results.

I know that, but the difference strikes me as too large for just that. Unless the benchmark forces use of RAM, I can't see where that would make a significant difference. But then they wouldn't be good CPU benchmarks.

Same CPU and likely same Intel chipsets, right?

The only purpose of the BOINC benchmark is to get a rough idea of the processor speed to know how much work to request. Beyond that it can be ignored. I let BOINC runs it's initial benchmark to set everything that it needs & then run with benchmarks disabled after that.

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