Re: Building a Media Computer
What you are trying to do is referred to as a htpc (home theatre pc). I have one, and it is very nice.
The biggest thing to ask yourself is if you want it to be capable of HD video playback. If yes, you should go with something along the lines of a Sempron 140 or athlon II, with at least a HD 4350 (no IGP!!!). If no, then I am sure you could find an old P4 computer on eBay for less than $100, and that would work fine.
As far as compatibility, the main things you should know are the socket types and what they support. AM3 is the one you will most likely be using. With an AM3 socket, you have two choices of mobo: AM2+/AM3 or just AM3. The ones that support AM2+ as well will be compatible with only DDR2. The AM3 only board will be compatible with only DDR3. I sugget you go with AM3/DDR3 because of the futureproofing it will give you.
Hope this helped. Feel free to ask any more questions.
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