Although Sandy Bridge's memory controller resides on the CPU, motherboards have some say in how that controller is tuned. To see whether that tuning produces any differences in memory bandwidth or access latencies, we ran a few tests with each board using the same memory speed and basic timings.
Nope. Well, not among the P67 boards, anyway. They all offer equivalent bandwidth and very similar access latencies.
CPU-Z measures access latencies in clock cycles, which features like Turbo make somewhat difficult to pin down. In this case, we've assumed that the Intel CPUs are hitting their peak Turbo frequencies during the latency test. We've also guessed that the Phenom II X6 in our 890GX system isn't reaching its Turbo Core peak, which appears to be a valid assumption based on how the results stack up versus what we've seen in more focused CPU reviews.
We measured system power consumption, sans monitor and speakers, at the wall outlet using a Watts Up Pro power meter. Readings were taken at idle and under a load consisting of a Cinebench 11.5 render alongside the rthdribl HDR lighting demo. We tested with Windows 7's High Performance and Balanced power plans.
Motherboard makers usually ship their boards with energy-saving features that promise to lower power consumption without resorting to CPU throttling that might hinder performance. The Gigabyte achieves this with Dynamic Energy Saver software, while the Asus 890GX offers a similar EPU app. That application isn't necessary with Asus' P67 board, which has an EPU switch right on the PCB. MSI's power-saving mode can be activated via the BIOS, so there's no need for extraneous software there.
We've tested the Asus, Gigabyte, and MSI boards with their power-saving features enabled and disabled. The Intel board doesn't have such a feature, so it only appears once in the graphs below.
So, that's why Intel didn't bother with a special energy-saving mode. The DP67BG draws fewer watts at idle than all the rest, and it has the second lowest power draw under load. Of course, the Intel board also has fewer onboard peripherals to power than some of the other P67 models.
Among them, the Asus and Gigabyte have the most to gain from enabling power-saving features, at least under load. There's little to no drop in idle power consumption with either. MSI's BIOS switch doesn't do much to reduce power consumption at idle or under load. That's not a problem at idle, but it does result in 10-20W more power draw under load than the rest of the P67 field.