Redditor shows an unusual PCIe adapter that allows you to take advantage of unused PCIe lanes, which are handy for adding extra M.2 SSDs.
Don't take your vacant M.2 slot lightly — it can do more than you think ...
The smallest PCIe slot on your motherboard is surprisingly capable ...
MY system is a Dell Precision T5610, which I like very much, but doesn't have onboard nVME slots. No big deal, I got a PCIe adapter and put in an m.2 nVME drive into it. Works great (OS is win8.1) but ...