Lenovo ThinkStation

I am considering the purchase of a Lenovo ThinkStation desktop computer.  It has to work with Sonar, a USB MIDI interface, a USB audio interface and a 5.1 speaker system.  Lenovo computers are not geared toward music applications but have plenty of speed, memory, etc.  The ThinkStation system specs say they work with 5.1 HD sound through a Realtek ALC662 codec.  However, they have a single 1/8" mini-plug line output, whereas 5.1 speakers utilize three 2-channel outputs (front L & R, rear L&R, center & woofer).  Here are my questions:
 
1.) Would a computer of this type be a wise choice for music applications?
2.) Is there some way that 5.1 HD works with only one line output?
3.) If the answer to #2 is NO, then what type of sound card would be necessary to achieve what I'm looking for?
 
I ask #3 because I was under the impression that my USB audio interface -- a FocusRite Scarlett 6i6 -- IS my sound card for all intents and purposes but it does not have 6-channel output; it has two sets of stereo and the unit does not decode stereo to 5.1.
 
Thank you for any advice you can give on this.
UCG Musician

No, the 6i6 only has 4 monitor outputs, essentially left and right channels going to two sets of stereo speakers.  As I understand it, 5.1 surround sound is simulated by sound cards or software.  The 6i6 has neither the required number of outputs nor a 5.1 simulation feature.

Lenevo should be fine for most work, depending upon the cpu etc.  The faster the chip, the more memory and dual disk drives will make your music life so much better.  The Focusrite is good, too, from what others say here.  When you get the exact specs fly them by in the computer forum and they will let you know.
 
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