How much are you willing to pay for improved power consumption and lower thermals? If you're a home cinema addict, reduced noise and smaller form factors are certainly desirable. For a price, the AMD Phenom II X4 905E promises to make all that possible.

Like its Athlon II X4 610E sibling, the 905E is a low-power variant of a familiar AMD processor. In this case, it's the full-on Deneb die found in high performance processors like the Phenom II X4 965 Black Edition. You therefore get all four cores and the full 6MB of L3 cache memory.

What you don't get is high clockspeeds. The Phenom II X4 905E runs at 2.5GHz. However, it's also rated at 65 Watts. That's a small fraction of the 140 Watt TDP of a high end quad-core AMD processor.