ECC Server RAM can be found dirt cheap on ebay, since enterprises use it and toss the stuff on a regular basis. You could easily fine 128Gb of ECC DDR4 for like

ECC Server RAM can be found dirt cheap on ebay, since enterprises use it and toss the stuff on a regular basis. You could easily fine 128Gb of ECC DDR4 for like $800. If you find an older (but still extremely powerful) Xeon that takes DDR3, you can get the stuff for pennies on the dollar. It's also quite easy to run a hackintosh on Xeons, if that floats your boat.