Seems a bit over the top in some respects...
1. Nice case... Sometimes smaller is better. Check out the Lian Li PC-36
2. Good motherboard, have it in my workstation. A good M-ATX multimedia board should be enough.
3. CPU overkill... C2D is plenty. One of the new low power C2Ds or a 45w AMD CPU would be good.
4. Smaller PS would be Ok. High efficiency is good. Efficiency varies with load so "right sizing" is important.
5. I would get a Hitachi Deskstar P7K500. It uses half as much power.
6. Video card looks Ok for video but seems out of line with other components. The GeForce 8500 will not do things like games well (if that is your plan.) I would go with an 8600GT or 9600GT or just use on-board video.
6. On board HD audio should be fine.
7. Omit speakers and connect it to an Home Theater. That is, unless your plan is to use a 24"+ wide screen monitor to watch video...
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