the A64 isn't as much as people think now a days. you can get an A64 and NF3 250gb combo from mwave for ~ 200. thats a kick ass pair and you get a decent OC out of the chip, although you said you dont want to OC. below that you'd do well with a mobile barton 2500 or 2400 which can OC to 2.6ghz. really OCing isn't nearly as big of a deal as most poeple think. its something you just gotta try, and then you'll prob never go back.
good luck