Rikki,

My apologies for not answering sooner, somehow I missed this post. I am not very experienced in the area of sound cards and latency and can only offer what I have read. I own the Presonus Firebox which is a firewire interface. I purchased it because I had been told that firewire was faster than usb.

However upon further investigation I find that it is a rather complicated issue. While Firewire can be faster, Firewire is listed at 400Mb/sec Firewire2 at 800Mbs/sec and USB1.1 at 12 Mbs/sec USB2.0 at 480Mbs/sec; other issues may need to be considered.

USB, or universal serial bus, may have a cost advantage as it is a master-slave periphiral network that relies on the processing power of the host computer to handle the data transfer; while Firewire is a peer-to-peer network that contains "smart" chipsets that allow any device to be host, so it does not tax the processing power of the computer's cpu. Firewire devices can actually connect and exchange data without a computer. This capability results in a more expensive chipset.

USB may be more common and easier to find. Firewire may have some performance benefits especially if your cpu is already over-taxed with other duties. Either will probably allow good performance.

If you are getting a 3ms latency with your external card, that seems to be a good solution and probably undetectable. I think the asio driver will be necessary as the windows driver is more general purpose and not suited to pro audio.

You may have already moved past this question because I am replying late and this could all now be a moot point. Anyway I hope this info helps somehow.

[This message has been edited by richard_shiflet (edited 12-10-2006).]