this may be an old post, but, i don't like seeing incorrect information
disreguard that reply above ... someone doesnt know what they are talking about
laptops these days are generally upgradable in the cpu department ... not many options, but usually upgradable
and cpu's are not soldered on ... they are socketed
the celeron 585 should be upgradeable to a T5850 Core 2 Duo ... you'll need to check around online and see if others have successfully done this with the same model ... sometimes a bios may not have the info in it to properly recognize your cpu, depends on the manufacturer ... but if they use the same mainboard in another model, within the same family persay, but with a Core 2 cpu, then your answer would be yes, you can upgrade.