USB performance
Our USB transfer speed tests were conducted with a USB 2.0/Firewire external hard drive enclosure connected to a 7200RPM Seagate Barracuda 7200.7 hard drive. We tested with HD Tach 3.01's 8MB zone setting.

The A8N32-SLI's USB transfer rates are faster than those of the NF4 Ultra-D, but they don't come cheap. CPU utilization during USB transfers is much higher for the Asus board.

Firewire performance
Our Firewire transfer speed tests were conducted with the same external enclosure and hard drive as our USB transfer speed tests.

Not much to see here. Move along.