Motherboard peripheral performance
Some of the biggest performance differences you'll find between motherboards come on the peripheral front, where it's easy to spot where mobo makers have skimped on auxiliary peripheral chips.

Poor Gigabit Ethernet performance seems to finally be a thing of the past, at least on high-end Core i7 boards. The Eclipse and UD5 are evenly matched here, with the former consuming a few more CPU cycles than the latter. Both use similar Realtek networking chips, but the Gigabyte board features newer RTL8111D chips to the MSI's RTL8111Cs.

While we've managed to avoid shoddy networking implementations this time around, some Firewire solutions are clearly superior to others. The MSI board's Via Firewire chip is faster across the board than the Texas Instruments chip used by the EX58-UD5.

USB performance is pretty much a wash, which is expected given that all four boards tap the same ICH10R south bridge chip.

The ICH10R is also responsible for close scores through much of our Serial ATA testing. However, there are differences in performance between the auxiliary SATA options offered by the MSI and Gigabyte boards. Despite the fact that both are essentially using a similar combination of chips, the Eclipse boasts higher read and write speeds. I'm not quite sure what to make of the incredibly high burst speed of the Eclipse's JMB322-backed SATA ports, though. These results were consistent across multiple test runs, and while the high burst rate suggests the use of cache memory for the auxiliary SATA controller, there are no memory chips on the board.

The EX58-UD5 does well in our 24-bit/192kHz RightMark Audio Analyzer loopback tests. However, despite its fancy X-Fi riser card, the X58 Eclipse scores quite poorly. RMAA identifies inter-channel leakage as a major problem for the X-Fi in loopback tests that route stereo output into the card's line input, and while that's something we've been able to correct with full X-Fi implementations, the lack of a robust audio control panel on the Xtreme Audio prevented us from doing so here. Fortunately, inter-channel leakage doesn't seem to affect standard audio playback. We listened to a few high-quality MP3s on both the Gigabyte and MSI boards, and it was difficult to discern obvious differences in playback quality between the two.