I have been running my 2010 Mac Pro 5.1 all original except for a ram upgrade to 64gb and changed the GPU to a Gigabyte RX 460 4gb. I have been running this setup since Sierra with no problemas whatsoever. With the most recent 10.13.2 update... it broke the sleep function what the heck apple ???!?! I put the Mac in Sleep mode, the screens turn off as usual and it seems that the Mac Pro enters sleep mode, but not totally. The power light slowly blinks as usual, but all the fans stay on. To top it off... only with a hard shutdown allows me to boot it up back again. Anyone else with the same problem? I suspect it may be graphics card related.. maybe they changed the drivers ?