It's not worth it, honestly. Save the cash and put it towards a desktop. Gaming desktop, surfing laptop. If you do it the other way around your gaming will suffer and it will be prohibitively expensive. If your other components can't keep up with your processor it doesn't really matter how fast your Turion is. Unless you just want it for Folding@Home.
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ASRock M3A785GMH/128M
Phenom II X4 925c2 @ 2.80GHz (95W)
OCZ Platinum PC3-1333 2x2GB 7-7-7-21
WD5000AADS
Raidmax RX-500AF
Check it out.