Hello I'm Leandro from Argentina, im trying to upgrade a mac pro 5.1 with 2 CPU Xeon E5620. My OSX is High Sierra 10.13.6 (17G6030). And i just got the gtx 970 sc ACX2.0, and followed all directions to install the web driver downloaded from https://create.pro/nvidia_drivers , and nothing, black screen. I try all Install Web Driver version 3184.108.40.206.40.127, which is compatible with macOS Sierra 10.13.6 (17G6030) that I'm running. Install latest CUDA driver Restart Choose to use the NVIDIA web driver in the menu bar, when let me choose to restar, i put "later" Then I Shutdown Install card and power cables Turn on the machine At this point, I could still hear the start up chime, but I waited and waited and there simply was no signal to the monitor, also I try all ports, DP1, HDMI, and both DVI. I popped the old card back in and started trouble shooting. Here's what I tried I ScreenShare with my Macbook Pro, and realize that theNvidia Drivers its not on. I cant set it. I try via terminal with "sudo nvram nvda_drv=1" restart, and nothing. I try to set again and restart, directly from the nvidia panel, and nothing. I try SIP disable and all again, Nothing. I try the card on a regular PC and founds correctly Moved the card to the 2nd PCIe x16 slot. No signal either I now have the HD5770 back in, and everything is good so far, but I really really want to use the 970 and High Sierra. I've done everything I can think of. Do you guys have any suggestion? Thanks!