I remember being so excited when I figured out how to jumper my DX/4 100 and operate it with clock doubling and a 50 MHz front side bus speed. Same core speed, faster memory and I/O.
My peripherals seemed to take it. My graphics output showed some slight glitches, which I was OK with for the speed.
However, I think it was a bit unstable and would fail a correctness challenge like compiling XFree86 or the Linux kernel, which were like overnight long runs. Must have been some bit flips in there occasionally. I seem to recall that once that reality settled into my brain, I went back to the clock tripler config.
I still remember scribbling on Athlons with a pencil to max them out - we probably spent as much on heatsinks as we saved on CPUs.