Well, I bought the beast! Thanks guys for your insight!
Since it's bought & paid for, I guess I don't have to worry about someone sniping it out from under me. https://www.ebay.com/itm/163491313811
Though I did notice after I paid, that seller has "Relisted this item or another one like it". Damn... I looked at his other items and selling history before I bid, no prior on this and only a few other computer parts, MBs & such; like you would expect from someone selling their old gaming rig.
Jeebus, I sure hope he wasn't just unloading some effed-up mining cards.?