Mobile Athlon Alternative
Right now the chip to get is the "mobile Athlon":http://forums.anandtech.com/messageview.cfm?catid=29&threadid=1321894 as this great thread describes.
There are four flavors so it is very confusing. There are:
* 1.2V Mobile Athlon 2800+ and 2700+ running at 1.8 and 1.6GHz Newcastle respectively. These both have 512KB cache and should overclock OK to 2.4-2.5GHz. The 2800+ looks like a good one. These are 32 watt chips so nice to use Quiet N Cool to overclock them when needed.
* 1.4V Mobile Athlon 3000+ and 3200+ that are ClawHammers running at 1.4V. A bit of a strange thing since most of these normal desktop versions will undervolt to 1.4V so not a great buy. Undervolting them is nice. Not clear why you need these since with Quiet N Cool, the system automatically undervolts to 1.1V anyway.
The main advantage of the Mobile Athlon 64 3200+ is that it is a 2GHz/1MB cache ClawHammer while the current retail Athlon 64 3200+ is a 2.2GHz/512KB cache, so you can overclock the mobile higher and the cache provides you with 5% more performance at any given frequency.
If you get one, you have to get the right heat sink since it (like the older Athlon XP) doesn't have a heatspreader cap on it. The Thermalright XP-90 works fine for this purpose.