Most cases come with a power supply but I wouldn't trust it. Most cases come with a cheap off brand power supply and ether die with in a year or isn't enough to power the whole system.

Here are the main brands to look for.

Ultra
Logisys
Aerocool
Thermaltake
Zalman

If you want to go cheaper use Rosewill. A lot of people don't like Rosewill but every power supply I have used by that company has worked fantastic.

Only reason why I mentioned the SSE3 thing is for just in case if some one else decided to follow this thread to build their own but using sub-par hardware.
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