Yes, P3 cores crack just like t-bird cores... They're a tad less susceptible to this, but they can too be cracked.
As far as the clip, be careful with it... DOn't force it, and make sure it is resting flat on the chip when you're clipping it in. Don't be worried if you have to "loosen" the clip. It is a very strong(high-pressure) clip, even for socket A use.
Mike