In researching a new PC for CS5.5 I saw a reference in a thread that there's something in the i7 processor that will speed processing over i5, i3 and the AMD processors but it didn't say what it was. This processing speed boost came from hyperthreading (as I recall) and manifest itself in improved rendering times. I searched both here and on the Adobe site for additional insight without success.

I don't want to incite a grand "which-processor-is-better" thread but anyone who has details about this and could share would have my undying gratitude for at least a week!

Richard,

Premiere Pro CS5.x does perform better on a system that has more cores on the CPU and supports more threads. This is called performance scaling in multithreaded applications. The desktop i7 CPUs have eight or more threads while the i5 and i3 CPUs are limited to four threads maximum. Plus, all desktop i7 CPUs have at least four physical cores while some i5 and all i3 CPUs have only two physical cores. Some i5 CPUs do have four physical cores - but without HyperThreading, they are as limited in multithreaded support as the i3 CPUs and the dual-core i5 CPUs.

The AMD CPUs, on the other hand, underperform in CS5.x - but for a different reason: The AMD CPUs do not support SSE 4.x instructions, which Adobe makes very good use of. Only Intel CPUs, dating back to the first Core 2 Duo CPUs of 2006, support at least SSE 4.0. The SSE support in all current AMD CPUs is limited to SSE 3.x. Adobe recommends, but does not require, SSE 4.x support; if Adobe had required SSE 4.x support, the AMD CPU-based systems would not have been able to run Premiere Pro at all.

Randall... Thanks. Great explanation. I know that it's hard to make generic head to head comparisons between Intel and AMD. But understanding how each of them work helps break through the clot of data points. Thanks again.

Have a look here: Benchmark Results (http://ppbm5.com/DB-PPBM5-2.php)

Select the tab 'Model CPU' and select i5 series. Notice the best i5 has rank 58 and the rest are way behind.

Next select Phenom series and notice the best Phenom had rank 162.

Now compare it to the i7 series and you see enormous differences versus i5 and Phenom. Randall explained the reasons to you, but this page shows you what it means in practice.

The best Phenom is 3.7 x slower than the best i7 system. The best i5 system is more than 2 times slower than the best i7 system.