from what i've heard, yes, you can boot with cheap ram and manually set the CAS and vdimm. I'm banking on this working for my OCZ Platinum PC2 6400. For the cheap memory, just make sure it's something like DDR2-533, cas 3, vdimm 1.8V. a 256MB stick should work fine. Also, I've been told that updating to the F4C bios (i think it's in beta, search the forums here or google it to find it) fixes some of the problems, but obviously you'll still need the cheap ram in order to boot the pc and update the bios.
all of this sure is a pain, but hopefully the OCing potential will make up for it.