I'm finding the comments in this post about Prime95 very interesting. The P4 guys are always hollering about 'I'm booting at 185 fsb on default voltage!', or talking about being Prime stable at 190 fsb. But where's the beef? Strangely, they never post any 3dMark scores.
What I do to test stability is run 3DMark2003, 3DMark2001, 3DMark2000, PCMark2002, IL-2 Sturmovik demo track, Serious Sam 2nd Encounter demo loop, UT2003, Codecreatures, then finish up with a SuperPI 16M run, which usually lasts a good 30' on a 3 gig P4 CPU. I have 4 rigs and since I change boards a lot, they aren't hooked to the net so I can't run Prime.
I have found some overclocked systems will pass 3DMark2003 but have trouble with 3DMark2001 or 2000, or vice versa. So 3DMark2003 passes at 180 fsb but I have to drop 1-2 mhz down to pass 3DMark2000. I've had rigs that passed all the 3DMarks but lock in IL-2, which is usually associated with SuperPI failing. Or I've passed everything but SS 2nd Encounter has an illegal op that means the CPU needs a tad more voltage. I finish up with SuperPI as a quick-and-dirty Prime.
But for sure, when these guys claim they are running 190 fsb at default voltage (big deal with P4s, like running 2500 mhz at 1.7 volts on an Athlon), I bet ya they can't pass all the above.