ronin667 Posted July 11, 2016 Share Posted July 11, 2016 Hello everyone, at first I have to admit, it is NOT my intention to build a PC to install OS X on. If that disqualifies me from asking questions on this forum, then please tell me and I'll leave the forum immediately. My problem is that I have an old Mac Pro 3,1 (early 2008) that was originally shipped with a nVidia GeForce 8800 GT. The graphics card died a few years ago. I replaced it with a Radeon HD 7770, mainly because the GeForce 8800 GT with EFI support was hard to get and still expensive, and I didn't see a point in buying an outdated overpriced card. Of course, I had to upgrade to Mavericks because the original Leopard didn't support alternate graphics cards. Now I have to upgrade to El Capitan for various reasons, but I've found out that El Capitan doesn't support the HD 7770. Installation of El Capitan runs fine, but once I try to start the system, all I get is a garbled screen, as seen in this video: https://youtu.be/hZlFPKbhhpE After some research, I found out that Apple apparently dropped support for the HD 7770 with some release of Yosemite. However, while searching for a solution, I found a lot of comments that people have successfully managed to get the HD 7770 to work with El Capitan on custom-built PCs. I was wondering if some of the techniques, like suitable .kext's, used for that could perhaps solve my problem as well. Is it worth trying? Link to comment https://www.insanelymac.com/forum/topic/313080-request-for-help-real-mac-pro-31-2008-el-capitan-radeon-hd-7770/ Share on other sites More sharing options...
savioparete Posted July 11, 2016 Share Posted July 11, 2016 try this kext for 7770 Verde.kext.zip Link to comment https://www.insanelymac.com/forum/topic/313080-request-for-help-real-mac-pro-31-2008-el-capitan-radeon-hd-7770/#findComment-2251374 Share on other sites More sharing options...
ronin667 Posted July 13, 2016 Author Share Posted July 13, 2016 Hello savioparete, thank you very much, however I'm not sure what I'm supposed to do with this file. Searching for the file name in this forum, I found some comments suggesting that the file should be injected into the Clover bootloader. However, I'm not using Clover as a bootloader, and as I understand this isn't even possible on a real Mac. Should I try and install Clover? Anyway, I've already tried to copy this file into /System/Library/Extensions, but it doesn't seem to get loaded on any point during boot. Sorry if I sound clueless on this but having an original Mac, I've never had hhe need to employ such techniques. Link to comment https://www.insanelymac.com/forum/topic/313080-request-for-help-real-mac-pro-31-2008-el-capitan-radeon-hd-7770/#findComment-2252418 Share on other sites More sharing options...
savioparete Posted July 14, 2016 Share Posted July 14, 2016 download kext utility and drag and drop verde.kext in the dialogue box.. insert your system password and wait done processes. enjoy Link to comment https://www.insanelymac.com/forum/topic/313080-request-for-help-real-mac-pro-31-2008-el-capitan-radeon-hd-7770/#findComment-2252604 Share on other sites More sharing options...
ronin667 Posted July 16, 2016 Author Share Posted July 16, 2016 Thank you savioparete, but the problem still persists. El Capitan refuses to load the Verde.kext because the signature is not OK. sudo kextutil Verde.kext gives me the error "untrustes kexts are not allowed". Interestingly, I was able to get normal video output, if I wait for the system to go into standby mode and then wake it back up. On the login screen, the display still appears still slightly messed up but usable enough to log in. From then on, everything works fine, OpenGL is available etc. But that can't be a permanent solution. Link to comment https://www.insanelymac.com/forum/topic/313080-request-for-help-real-mac-pro-31-2008-el-capitan-radeon-hd-7770/#findComment-2253349 Share on other sites More sharing options...
Recommended Posts