I have a spare Athlon X2 4000+ and a socket 754 board. I read that socket 754 supports AMD Athlon up to 3700+ but I was curious if anyone has been able to use a 4000+ on this socket..or is that just impossible?
A CPU will not work on anything but the socket it is designed for. It won't even fit in the socket. The exception of this is AMDs newer sockets: AM2, AM2+ and AM3. AM3 cpus are backwards compatible into AM2+ boards and some AM2 boards. AM2+ and AM2 are interchangeable.