I'm always checking the common sites for new gear, old gear, anything that comes to mind. However, I'm held aback since I'm not finding any AM2+ CPUs on Tiger, NewEgg, and essentially any other common site. Found ONE damn cpu on OutletPC I believe, AM2+, some old Phenom. Not bad, but only one on the damn net? Is everyone recycling inventory overnight? I wouldn't doubt it, but geez LET ME FIND AN 40-50 BUCK AM2+!
Indeed, the am3 chips have 2 memory controllers, one for DDR2 and one for DDR3 thus why they work.
If the rest of your system can handle it Phenom II x4 955 BE for example would be an excellent choice for an upgrade.
Just make sure to check for support for the CPU from the motherboard vendor, most likely you will have to upgrade the bios.