Convert Multicore processor speeds?

Posted by admin on Jul 6th, 2010 | 0 comments

Question by brian577: Convert Multicore processor speeds?
The specs for Left 4 Dead 2 say it needs a 3GHz Pentium 4 minimum, but recommends a 2.4 Core2Duo. How are single core speeds converted into multicore speeds?

Best answer:

Answer by Proto
They don’t translate directly- the design enhancements introduced with the original Core 2 Duos made them much more efficient at lower clock speeds than older Pentium 4 and Pentium-D chips. They also use less energy, generate less heat and overclock more readily.

Once Core 2 Duos arrived on the market, it was no longer possible to rank CPUs just based upon the Ghz rating, because other factors play significant roles in overall performance.

And of course applications are which are coded to take advantage of multiple cores (i.e. multi-threaded) see even greater benefits from dual and quad core CPUs than old single core designs.

As a VERY rough estimate, perhaps multiply by 1.75 (but that’s not really accurate). Basically, even the highest clocked single core CPUs don’t come anywhere near the performance of modern dual, triple and higher core CPUs.

For example, even the original 1.87Ghz Core 2 Duo was faster at performing single tasks than a Pentium 4 clocked at 3.6Ghz.

Here are the passmark rankings, which aren’t all that useful since apps which aren’t multi-threaded don’t run any faster on a quad than a dual core assuming they’re running at the same clock speed. But there’s a significant gap between either of those CPUs and a single-core.