Seems the Winbond chip doesn't support a variety of FSBs. I was looking at a P3B-F board the other day, and I notice it has a Winbond clock generator, which probably explains why they only go from 133 to 140 to 150 also.
I'm going to be swapping the 600E I got running at 144 FSB onto a couple of 440BX boards soon (P3B-F or BE6-II Ver. 2.0). One guy said that board is snappier than his PentiumIV. If it's an earlier PentiumIV, I don't doubt it.
I'm hoping I can take it up to 150, but I doubt it (already burnt it in).
The P3V4X is a real stable board though, since I got a 120 mm fan blowing over the ram and ICS chip (no heatsink yet). I had a P3C-E (intel 820 with rambus) in there earlier and though I hit about the same FSB and the board was really high strung and fast, it wasn't quite as stable (those annoying registry errors when booting into Windows).