If you're going to go to the trouble of reproducing a VRM, I would add a couple of enhancements.
At the very least it should have a trimpot for overclocking, and a jumper to set 487SX mode for motherboards that only have an overdrive socket (OEM systems had SX chips soldered to the board). Some but not all VRMs had this.
You might also want to consider adding some advanced stuff, like a jumper to set Ti486SXL pinout, and maybe solder pads in the centre for adding a Cyrix 87XLC FPU. FPU support for Cyrix 486S would be nice too.
But what I think would really bereally cool is if you could put a programmable IC on there so that you could set CPU registers for Cyrix 5x86 CPUs. Then you wouldn't have to run the configuration program during boot. Ideally you'd configure the chip from DOS, and of course there should be a way to reset things if you screw it all up.
"Will the highways on the internets become more few?" -Gee Dubya
V'Ger XT|Upgraded AT|Ultimate 386|Super VL/EISA 486|SMP VL/EISA Pentium