Well, during the overclocking portion of my upcoming review, I had a nice little problem: my shim was shorting out one of the components on the CPU package surface. One I removed it, I haven't had any problems so far! While the chip is unlocked, I did the L1 Pencil trick job on them just in case, but I'm pretty sure it was the shim. If you have a Pentium III, you should be okay with the shim, as there's nothing to short out.