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Will CPU clock rates decrease as the number of cores increase?

Hey all, sorry if this question is being asked in the wrong place. I couldn't find a "General Discussion" area and I know this forum is for software (which I'm actually a programmer at a game studio).

Since a large reason why CPU clock rates can't increase is mostly due to power cunsumption increasing, will CPU clock rates decline as more cores are added? Let's say we have a 100 or even a 1000 core desktop processor, will it be able to have 3+ GHz, or will it more than likely drop to something 1 GHz or even 500 MHz?

I've been curious about this for a while and it may be too early to know, but I'll ask anyway :)

Thanks a bunch,
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2 Replies
Black Belt
Thinking about the history of clock rates on recent desktop chips, I'm sure you could look up data points to show that clock rate goes down each time the number of cores (or width of parallel instructions) increases, then may largely "recover" with the next "process shrink." As there aren't yet any 22nm CPUs with more than 8 cores/16 hyperthreads (that I know of), it's premature to project trace size vs. clock rate into the future on the basis of current data.
If Nvidia is successful, it certainly looks like very large numbers of cores will be associated with clock rate decreases, but obviously, you can't compare clock rates between widely different architectures.
Power efficiency certainly will continue to grow in importance, not only for small portable devices, but also for Intel MIC and GPGPU type accelerators in desktops, where there is a practical total power limit to be spread over an increasing number of cores. Data centers nowadays certainly consider their power budget when planning increased capability.