No. I have it, but have not even attempted to overclock it at all. From what I've heard, you might get 300fsb out of it if you are lucky. I only got it to run SLI until the better 590 series comes out in a couple of months.
I can say, though, that once I finally got XP loaded on it (not a good time for me, it was the first time in hundereds of builds that I had major trouble, which ended up being operator error!), it has been extremely stable.
Nope, not really that bad at all. There are quite a few people that would disagree, however I am not one of them. I just wanted something to run my 7900gtx's in SLI and be stable. So far, the P5NSLI has held up very well for that purpose.