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well in windows (yes I know) my dual cores shunt all the lesser work (overheads) onto the other core when one core is being thrashed (well it actually sets both cores at around 50% but you get the idea). The overall speed of the single core encoded program is about 5-10% higher than if it was on a single core cpu of the same clock.

So say a 2.2Ghz dual core would be similar to a 2.4Ghz single core in single core operations.

What programs did you run? I'd like to see the overclock happening on my machine. I've tried a few apps, like super pi but using cpu-z the CPU never goes above 2.2 GHz.
 
So say a 2.2Ghz dual core would be similar to a 2.4Ghz single core in single core operations.

A single core of a dual-core processor is not the same as the rated clockspeed for the over-all CPU. Nor is it half of it.
 
A single core of a dual-core processor is not the same as the rated clockspeed for the over-all CPU. Nor is it half of it.

I never said it was. I know how multi cpu/cores work, I've been using them long enough :rolleyes:

I said
LeviG said:
well in windows (yes I know) my dual cores shunt all the lesser work (overheads) onto the other core when one core is being thrashed (well it actually sets both cores at around 50% but you get the idea). The overall speed of the single core encoded program is about 5-10% higher than if it was on a single core cpu of the same clock.

So say a 2.2Ghz dual core would be similar to a 2.4Ghz single core in single core operations.

which is in regards to non multithreaded/smp aware applications.

On a single core/cpu system all aspects of the programs/os are running together and being spread out over a single cpu/core.
With 2 cpus/cores (or more) the load of programs/os is spread over the 2, meaning a single core program (assuming only 1 program making full use of core) would receive 50% of the overall processing power while the spare 50% would be used to cover the os overheads. As such this would give the program an advantage over a single core cpu clocked at the same speed because the overheads are not on the same cpu/core.
 
^ Sorry I wasn't meaning to say you were wrong - I was just trying to point out to people incase they took your post in a different dimension.
 
I thought I read somewhere that part of the power enhancements of SR was to switch off one core when the AC is off?

Seperately, surely the management of the cores is done by the CPU management system, thereby being OS agnositc? I think (again I don't remember details so feel free to correct) the OS and userland software can provide hints or overrides to this to optimise. For example some apps are programmed to make fuller use of mulitple CPUs where available.
 
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