Originally posted by: f4phantom2500
Does it have to be AMD? Try to go Intel if you can, the Celeron M 4 series is basically a Core Solo with less cache (1MB). I don't know about the 5 series, I assume it (looks like there's only a 520 right now) is just 64 bit, as that looks like the only difference according to this chart
http://www.intel.com/products/processor_number/chart/celeron_m.htm. If 64 bit isn't a big deal I'd go with the 4-series but if so then 5.
Anyway, if it has to be AMD it looks like the only practical difference is the Turion has more cache. I would just get the Sempron since it's a $50 difference, spend the money on more RAM, but if it's within your budget spring for the Turion.