why the frequency of Tesla C1060 steps down on windows

Accelerated Computing CUDA CUDA Programming and Performance
1

there is a strange problem with my two Tesla c1060 cards. When they run on windows xp, the geometric frequency, the shader frequency and the foreign frequency all step down to about 60% of original frequency. Detailed data as follows:

now geometric frequency: 400MHz
original geometric frequency: 610MHz

now shader frequency: 799MHz
original shader frequency: 1296MHz

now video memory foreign frequency: 297MHz
original video memory foreign frequency: 800MHz

So the “bandwidth test” in quick mode illustrates that the device to device bandthwidth is just 73311MB/s, there is a big gap between the original bandthwidth of c1060(about 102GB/s) and 73311MB/s.

I have tried the latest driver(190.00 for tesla c1060 and 191.07 for GT200)

Thanks for your help!

2

yeah, it slows down when the card is not in use. when it is, it hits full clocks (always). BW test usually reports 73GB/s, I think because of its particular mix of operations and overheads.

3

Pretty much every card I’ve tested gets 70-80% of the theoretical memory bandwidth using bandwidthTest.