AMD Phenom II X3 705e and Phenom II X4 905e Processors

Power Consumption

Since power consumption is a big deal these days, we ran some simple
power consumption tests on our test beds. The systems ran with the
power supplies, case fan, video card and hard drive model. To measure
idle usage, we ran the system at idle for one hour on the desktop with
no screen saver and took the measurement. For load measurements,
POV-Ray 3.7 was run on all cores to make sure each and every processor
was at 100% load. Both processors were tested on a system using
identical hardware.

Results: The power supply that we have dedicated to just our CPU testing systems
recently failed and is no longer in production. Since we had to the
change power supply all the power consumption results of the processors
will have to be re-tested. For the time being we ran power consumption
tests on some of the AMD Phenom II processors the energy efficient processors run with very impressive power numbers. The AMD Phenom II X3 705e with three cores running 2.5GHz consumed just 1 Watt more than the AMD Athlon II X2 250 dual-core processor at 3GHz. Both the TDP on the Phenom II X3 705e and the AMD Athlon II X2 250 is 65W, so the load power consumption being so close makes sense.

The TDP on the AMD Phenom II X4 965 BE is 140W, which is higher than the 125W TDP rated previous Phenom II X4 955 BE processor. AMD informed us that the 965s idle power draw should be nearly identical to the 955 and while at load, overall system power draw on a high-performance rig should not change much (maybe ~10W delta at full load). Our test results showed a 23W difference between the two processors at a full load though. Every processor consumes slightly different amounts of power, so keep that in mind when researching energy efficiency. The AMD Phenom II X4 905e is a very efficient part and consumes just 174W at full CPU load on our test system. That is 68W less than the 140W TDP rated AMD Phenom II X4 965 BE!

The highlight of this chart is the AMD Phenom X4 9350e power numbers. This is a quad-core, 2GHz, 65W TDP part from last
summer. The The load power consumption on the AMD Phenom II X4 905e was actually 8
Watts lower than this part! This is crazy impressive as the AMD Phenom II X4 905e processor runs 500MHz faster on the core clock and with 4MB more L3 cache!