A 2.5ghz mobile would most likely be faster than an A64 2800+ on stock. However, I don't advise getting a mobile 2500+ barton. The overclocks on those still are questionable. Of the several I OC'd, a few of them wouldn't go past 2.4, while one of them I got to 2.61ghz. At this point in time, I'd have to say you should be buying a 35w 2400+ over a 45w 2500+. They are the same price, save a dollar or so, but the 35w chip is more consistent. No one needs to be buying the mobile 2500+ anymore.