ok it's been to my attention that the special HP/Compaq model of the Voodoo 3 AGP is, in fact, a Voodoo 3 3500 converted to have a standard VGA connector, and without the TV module on it. But then it's detected as a Voodoo 3 3000 at 166Mhz, so my guess is it must be safe to clock it back at 183Mhz  if it's really a 3500.

But now i wonder, which model(s) would it/they be?