Gigabyte H55N-USB3 : Mini-ITX done the Gigabyte way...

We utilized memory kits from Corsair and G.Skill to verify memory compatibility on our test boards. Our OS and primary applications are loaded on the OCZ Vertex 120GB SSD drive and our games operate off the WD Caviar Black 1TB drive. We did a clean install of the OS and applications for each motherboard. We used Intel's stock cooler for the stock comparison testing, while water-cooling via the superlative Heat Killer 3.0 water block was utilized for overclocking. For graphics duty, MSI’s GTX 275 Lighting GPU was used to provide performance comparisons between boards during gaming benchmarks.

For our test results we set up each board as closely as possible in regards to memory timings. Otherwise all other settings are left on auto. The P55 utilized 8GB of memory where possible, while the X58 platform contained 6GB. The P55 and X58 DDR3 timings were set to 7-7-7-20 1T at DDR3-1600 for the i7-920 and i7-870 processors at both stock and overclocked CPU settings.

We used DDR3-1333 6-6-6-18 1T timings for the i5-750 stock setup for all system benchmarks (non-gaming tests) as DDR3-1600 is not natively supported at a stock BCLK setting of 133. For our Clarkdale i5 661 and i3 540 CPU’s, we used 7-7-7-20 1N timings at DDR3-1333MHz with 8GB of memory (4GB on the Mini-ITX boards).

Power Consumption

Our power consumption testing utilizes the same batch of components under similar circumstances in a bid to monitor variances between idle and CPU load conditions. We install the vendor supplied power saving utilities on each board and enable power saving modes that don't involve any kind of underclocking or CPU core frequency modulation in order to run an apples to apples comparison.

ATX PSU switching losses are absent from our figures because we monitor power consumption directly at the DC rails of the PSU. These figures measure only the CPU, motherboard and memory DC power draw and exclude any other peripherals, such as cooling fans and hard drives etc. Actual AC power consumption for the motherboard will be anywhere from 15~40% higher than these figures depending upon the efficiency of your power supply.

The H55N-USB3's idle power consumption is excellent, although you lose out on efficiency under load compared to boards from Intel and ECS. We suspect this is due to Gigabyte's choice of a more robust VRM to aid in overclocking. The Intel DH57JG does not support Lynnfield processors, while ECS's model is confined to a 87W TDP cap.