Benchmark Results: A/V Encoding
Our MainConcept rendering test responds to both the threading and clock rate. The Core i7-975 Extreme doesn’t perform much faster than the 965 before it, but there is a marked benefit to adding 133 MHz.
Optimized for just two threads, the quad-core i7s with Hyper-Threading enabled don’t realize their full potential and are matched by Intel’s Core 2 Extreme QX9770. AMD’s 3.2 GHz Phenom II 955 trails behind the Intel chips.
Our results with DivX and Xvid are similar, but by different margins. DivX is able to take advantage of Core i7s four physical cores and the four virtual cores enabled by Hyper-Threading, thus allowing even the i7-920 to outperform the higher-clocked Core 2 Extreme and Phenom II. The Xvid test only taxes about half of the processor’s resources. So, while you still see the i7s dominating, Intel’s Core 2 Extreme and AMD’s Phenom II X4 are much closer to the rest of the pack.
Lame runs on a single thread, scaling according to clock frequency. Intel’s Nehalem micro-architecture gives is a significant advantage here, enabling the 3.06 GHz i7-950 to outperform the 3.2 GHz Core 2 Extreme QX9770 and 3.2 GHz Phenom II X4 955.