CPU utilization
RightMark 3D Sound measures CPU utilization with a variable number of hardware voices for 2D, 3D, and EAX audio. The ALC880 doesn't support more than 32 voices, so you won't find scores for it at 64 and 127. There are scores for the Audigy2 ZS and Revolution 7.1 at 64 voices, but we should note that the Audigy2 actually maxes out at 63 voices.

The advantages of hardware acceleration are readily apparent in RightMark 3D Sound, with the Creative cards easily consuming fewer CPU resources than the competition. Note that the X-Fi uses less CPU power with 127 voices than the M-Audio Revolution 7.1 does with just 64.

While running RightMark 3D Sound, we wondered if the X-Fi's 24-bit Crystalizer and CMSS-3D had much of an impact on CPU utilization, so we put the XtremeMusic through a few extra tests with various Crystalizer and CMSS-3D settings.

With the exception of CMSS-3DHeadphone, neither the 24-bit Crystalizer nor CMSS-3D appears to have much of an impact on CPU utilization. CMSS-3DHeadphone's CPU utilization doesn't really ramp up until we hit 127 voices, either.