Most pro audio interfaces worth anything use Firewire these days anyway (with the exception of RME and M-Audio's Delta series), so just disabling the onboard in the BIOS is adquate, you won't be going anywhere near it anyway. Be sure whatever motherboard you choose uses a TI (Texas Instruments) Firewire chip, and if it does not, buy a PCI card that does. It does make a huge difference, cheaper chips tend to be noisy, introducting pops and clicks into the audio signal, and in the case of really cheap chips, often lose the connection to the soundcard in mid-stream. A Xeon based board is an alternative, but expensive, and the processors required are near astronomical in price. It really depends on how far you want to go, though. I do just fine on a stock Q9550 and Asus board with the onboard disabled, and in fact was glad to have it when I started having a balance issue, was able to rule out my hardware and trace it to a simply replaced monitor amp.
Faster than the speed of snot
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