I just purchased a refurbished white iMac 2.0Ghz (iMac 5,1) to make use of my Logic Pro and Pro Tools licenses. Reason being, Logic 8 won't install on my MacBookPro with Retina Display. Despite being a Universal App, the installer is PowerPC only, and thus won't install on Mountain Lion. Pro Tools 8 was never certified for Mountain Lion. So, rather than to upgrade both Logic and Pro Tools, I bought a refurb computer for $229. It runs awesome, and I thought I may as well put my old FW 400 drives to use. Situation: I was trying to playback a complex Logic project (approx 30 tracks) and was having CPU load issues. However I don't think the issue was with the CPU specifically, I'm not sure if my FW400 drives (Lacie, 7200 rpm) are fast enough to stream that much audio. Questions: Is there a way to measure how much data it takes to stream a single track of audio (.wav, 48k, mono) ?. How many tracks are you guys able to playback over Firewire 400? Further more: Is there an easy way to split up my project media across 2 Firewire400 drives to take advantage of more bandwidth? I realize in hindsight that the iMac might not have been the best purchase. The CPU is perfectly fine but I forgot the main drawback of these old AIOs is the drive bandwidth with a lone os drive controlling the system!