going with intel in your budget and still leaving OverClocking option+ future upgrade is impossible . with going for intel you will get a realy cheap board and the same performance. the best cpu i can get for the same price your current one is the SB pentium G860, which will give you great performance but will leave you without the ability to either upgrade nor overclock.
if youre skipping the monitor+case you can get a nice 955BE with a more expensive board so you could have overclocking+future proofing.
bottom line is that amd did have a minor step down the last few years but the Phenom II series was nothing but succes , you can ask any phenom owner and he will tell you that it was the best buy of his life.
