Matching iMacs different cuda task speeds

Are the GPU's identical?

I'm assuming you are testing on the same W/U.

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You're only got two hosts on your Account, One running Windows 7 Professional x64, the other running Darwin 12.2.1, so i can't compare GPU tasks from one host to the other:

Computers belonging to Dan Stoneham

Not all MB tasks are of the same length, how long they take depends on the Angle Range,

Very High Angle Range tasks where the telescope is being swept across the sky take the shortest time to complete, about 2 minutes on my GTX460,
Normal AR (~ 0.44 AR) tasks where the telescope is static, but the earth rotates, take about 8 minutes on my GTX460,
Very Low Angle Range tasks where the telescope is pointed at a fixed point in space, take something like an hour or two to do, because of this they aren't sent to GPUs,
you can also get tasks that have an AR of 0.37 that take an extra minutes or two, and tasks outside the defination of VLAR that take extra time too,

Claggy

You can keep HT enabled on i7 and limit the CPU to use 50% of processors. This way you have maximum number of CPU-FP units utilized and those extra HT cycles (cores) are reserved for GPU tasks requiring CPU for memory transfer/logic.


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