The "no stress on your computer" description is not completely new to HD - it's one of the primary benefits of using Digidesign's dedicated hardware DSP acceleration (rather than just host-based processing). The part that's new with HD is that we doubled the macimum track count at 48 kHz from 64 tracks to 128 tracks.Additionally, even at the higher track counts, the HD cards are more immune to -6042 errors. There are multiple reasons for this: First the PCI hardware interface is better (things like automatic transaction retry are incorporated into the hardware). Second, the new DSPs on the HD cards have more internal memory, and the DSP engine code has been optimized to take advantage of this so that larger PCI bursts are now possible (this was a big limitation with the DSP chips on the MIX cards). The end result is that high tracks counts are possible with very little impact on your computer (especially the host processor itself).