AMD's 65nm Brisbane Core Previewed: The most energy efficient AMD CPU to date

The Test

Performance-wise, the new Brisbane chips shouldn't be any different than their 90nm counterparts, but to make sure we benchmarked the new chip against our first 90nm X2 5000+. From a power consumption standpoint, we wanted to compare the new 65W 65nm chip to AMD's Energy Efficient and Energy Efficient Small Form Factor 90nm chips to see how the new process competes with the most efficient of AMD's CPUs that use the older, but more mature process. Unfortunately, we only have a 5000+ 65nm chip, so we can't say for certain what advantages Brisbane will hold at equivalent clocks to the EE/SFF parts.

For each benchmark we measured performance as well as average power consumption during the course of the benchmark, finally reporting performance per watt as one divided by the other.

Before we get to the power consumption tests let's have a quick look at idle power consumption of these systems:

Note that Cool 'n Quiet and EIST were enabled for all tests, but running at 1GHz the AMD CPUs at idle are able to draw much less power than the Intel system (which runs at an idle clock speed of 1.6GHz). Part of the increased power consumption for the E6600 may also be due to the 680i chipset vs. the 590 SLI used on the AMD systems, but we would need to compare both chipsets on a common CPU platform to be sure of that.

Regardless of the reasons, at idle, our Intel test platform consumes much more power than any of the AMD platforms. At the same time, the new 65nm Brisbane CPU doesn't really draw significantly less power than the 90nm cores at idle. Under load though, we've got a completely different story...