Freebase Dali

The 2626 IS a soundcard.
All you have to do is take the unit out of the box, install whatever software/drivers that come with it, power it up and plug one end of your firewire cable (which you'll probably have to buy separately) into firewire port 1 on the back of the audio interface, and plug the other end of the cable into your firewire port on your computer.
You can go ahead and disable your PC's built-in soundcard, as your new 2626 will be taking over that role, but in FAR superior quality, obviously.

The only thing you must determine is if you have a firewire port on your computer. (see the end of this post for a picture)
If you DO have one, you may want to make sure the firewire controller driver is installed and active. You can do this by right-clicking "my computer" or "computer" if you're in Vista, then "manage", then "device manager". On the right hand side, you should see "IEEE 1394 Bus Host Controllers" or something to that effect, then expanding that will show the manufacturer. Verify whether it says the driver is installed and functioning properly. After that, you can close all that out and you don't have to worry about anything as far as hardware is concerned.

IF YOU DON'T have a firewire port, this is what you need: Newegg.com - SIIG 3-port 1394 (FireWire) I/O card Model NN-300012-S6 - Add-On Cards
You can shop around for different products, especially try to find one with a Texas Instruments chipset, but the above product will let you know what to look for. You really only need one port, but most firewire cards come with two or three, so don't worry too much about that.

So, to re-cap.
All you need is the firewire card if you don't have one, and the audio interface. After that, it's simply a matter of plugging in your microphones and whatever else, and opening up your recording program, selecting which inputs you want to route to which channels, and hitting the record button. (generally)

Now, I probably don't have to say this, but hopefully you have a recording program that facilitates multi-track recording and provides the ability to assign your audio interface's inputs to specific channels to record into.
Examples of these types of programs would be: Cakewalk Sonar 8, Pro Tools, etc.
I'm assuming that you either have a multi-track recording program, or know that you need one.. because without one, you're not going to get very far with an audio interface without having the software to record the audio coming through your interface.

Firewire port:

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