My PS3 Gibson guitar will not work with PS2 Guitar Hero games being played on a 60GB PS3. The 6 axis controller does work, but is not appropriate. Will a PS2 guitar work? Will I need a PS2 to PS3 adapter as seen on eBay?
Different models of PS3 have different levels of compatibility. Have you downloaded all updates for your system? Many updates deal with compatibility, so it's worth a try. I would only get the adapter from a place you could return it to if it doesn't work.