they are both ***... they are acers to start with and they have crappy chipsets. one has a SIS and the other is a 6100 nvidia. the AMD has the nvidia chipset so thats the better MB but the SIS chipset has the core 2 duo, however it can not go to a core 2 quad.
just sell them for a few hundred and build new. you can build a comp 100 times those for less than 600 on a budget. with alot more upgradability in the future.