So my question is simple... after some simple research am3 is compatible with am2. However, my question is that my motherboard supports 89w processor. Which i currently have an am2 89w Athlon x2 5400+. I just purchased a am3 125W processor "phenom 11 955 be @ 3.2ghz" .
Even if the sockets are compatible does this wattage make a difference in what the motherboard can handle? Will it work in this motherboard?
Most likely YES - if the 89 Watt is the max the MOBO supports then it is likely that the MOBO does not have the circuitry to provide 125W to the CPU socket (probably does not have a seperate 4 or 8 pin CPU power connector to provide the extra power as well - so you will probably need a new MOBO to run that cpu.
Best bet is to check the MOBO makers Website to check the CPU compatibility list to make sure but I would think it is not going to be supported !!
Definitely check the CPU compatibility list for your motherboard on the manufacturers website.
If you try to run a higher power CPU than what is recommended the voltage regulation circuity may not have sufficient cooling for the extra power and could over heat and fail, killing the motherboard and potentially the processor too.