you can upgrade to the 4600 a10 trinity but not the richland I believe...just do a bit of googling on it and search youtube, I looked into it awhile back.
You can actually replace a lesser cpu laptop with a better one in the same class. For example I thought about upgrading my sucky old single core sempron that struggles with win7 laptop to a dual core turion cpu, but just didn't feel like it...threw linux mint on it lol.
but the improvement probably isn't worth the trouble....I'm not a fan of gaming on laptop at all...this AMD apu llano a8 I have right now gets boiling hot playing any game even with a cooling pad on it...it's strictly an internet browsing/streaming laptop now...kind of a waste since it's a decent quad core laptop cpu, thing just runs way too hot, it burns my fingers gaming lol.