There are hosts of different processors out and about, so a basic guide is:- Avoid the reduced function range, i.e. sempron / celeron, these are aimed for the cheap end of the market and will offer much reduced performance. Centrino, is as PJF mentioned a badge awarded for having a certain set of bits in your laptop - in truth it's a very effective maketing gimic as there are lots of other chipset combinations that are as good, but the centrino badge makes it easy for joe on the street to believe they're getting a good laptop. 64 bit is good. high speed numbers are good (4800+ etc). look at dual core units (x2 in AMD speak or D in Intel speak) If you want to get a high speed laptop, they will be heavy and hard to carry around. Alienware and Boxx both do top notch laptops suitable for graphics use, consider adding a laptop cooler to you shopping list. IMHO AMD are better chips.

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