At 3 GHz, the Core 2 Duo E8400 is right in the middle of Intel's E8xxx range. 

On paper, it's 10% slower than the the E8600, the 3.33 GHz processor at the top of this line, but our tests showed that it was only around 8% less powerful.


The discrepancy was only visible in some of our tests: playing 3D games, for instance, produced an acceptable framerate, but our 2D graphics test which involves applying a filter in Photoshop CS3 showed a wider gap between the two processors.

The E8400 took 4 minutes 31 seconds to do a task that only took the E8600 3 minutes 53 seconds.

For that reason, we prefer to recommend a CPU with four cores, like Intel's Core 2 Quad Q9650, which completed our 3D rendering test in 1 minute 15 seconds compared to the E8400's 2 minutes 22 seconds, despite both processors having the same clock speed.

The E8400 is fairly reasonable in its power consumption given how much performance it delivers, but it's a long way from being an energy efficient processor.

Up against Intel's great rival AMD, the Phenom X4 9650, a quad-core processor, comes close to the E8300 on certain tests, but their respective performances are too close to give a definitive answer about which one is better.