In the wake of our Athlon X2 BE-2350 review, the folks at Intel contacted me with a challenge. We had tested AMD's new low-power processor with a motherboard based on the AMD 690G chipset and found the combination to be exceptionally power efficient. We had not, however, tested Core 2 Duo E4300 alongside Intel's G965 Express chipset, which also packs integrated graphics and a low power footprint.

We'd neglected to test this config in part because, honestly, we didn't expect the G965/E4300 combo to deliver results in the same class as the X2 BE-2350/690G pairing. Some of our previous tests had suggested that motherboards based on the G965 chipset drew more power than AMD 690G boards.

Intel confidently claimed its solution was competitive, though, and suggested we test and see for ourselves. That only seemed fair to me, so I decided to give it a shot.

The results are below. We tested the E4300 on an Intel DG965WH motherboard with the same basic configurations and methods used in our Athlon X2 BE-2350 review, logging power over time while the system rendered a scene in Cinebench using multiple threads. I suggest looking over that review for complete info on how we tested.

I've included results from several different Core 2 Duo E4300 configs, including:

• Our stock Core 2 system based on the 975X chipset with a GeForce 7900 GTX graphics card

• A system based on the G965 mobo with this same graphics card

• The G965 system using its integrated graphics processor (IGP) instead of discrete graphics

You can compare the E4300 to other Core 2 Duo processors by looking at the first set of results. The second set, with discrete graphics on the G965 board, gives us a sense of how this motherboard's power use compares to our default 975X board. The true low-power config, of course, is the third one using the G965 integrated graphics. For comparison, we have a similar constellation of AMD setups involving the Athlon X2 BE-2350 and the chip it replaced, the Athlon 64 X2 3800+ Energy Efficient Small Form Factor.

We'll start with a graph of the raw data over our 60-second test period.

You can see right away that the E4300/G965 combo with integrated graphics gives the AMD systems a run for their money. The Intel platform uses a little more power at peak and at idle, and the E4300 takes a tad longer to render the scene, but the contest is a close one. Let's slice and dice the data and bring our whole range of CPUs into the mix.

The E4300/G965 team draws only 5W more at idle than the XE BE-2350/690G.

When the CPUs are busy rendering the scene, the gap between E4300/G965 and the X2 BE-2350/690G narrows to 4W—closer than ever.

The difference between the X2 BE-2350/690G and the E4300/G965 in total energy consumed over our 60-second test period adds up to about 400 joules—not a lot in the grand scheme, especially considering that the worst offenders are consuming 10-15K joules during this span of time.

The gap between these two configs in energy needed to render the scene is also about 400 joules, and again, it is a proportionally small difference, though not insignificant.

These results don't really alter our original estimation of the Athlon X2 BE-2350 and 690G chipset combo. AMD has achieved a smaller power footprint than the competition by offering a CPU specifically tailored for low-power applications, and we're pleased to see that development. At its price, the BE-2350 remains a bargain.

We've learned, however, that the Core 2 Duo E4300 and G965 chipset can also form the nucleus of a very power-efficient system, one that nearly rivals AMD's low-power desktop platform. That's true in spite of the fact that the Core 2 Duo E4300 isn't billed as an especially low-power part like the Athlon X2 BE-2350 is. That's an impressive result, in my view, and a testament to the overall power efficiency of Intel's standard desktop Core 2 Duo processors and their supporting chipsets.