So an update, I’ve ordered some different 6-8pin connectors to see if they make a difference after my initial, failed attempt to run the Radeon VII 16GB Sapphire on a HP Z620. The HP certified 6-8 pin gpu power adapters will arrive tomorrow for my final test to ensure that the power being supplied to the Radeon VIi card is used with the HP certified adapters that don’t come cheap!
So my testing has been as follows:
i tried a clean install of windows 10 Pro 1903, it installed to the end and allowed me to reboot to desktop. Once there, it was a matter of time before the smallest task like launching the start button caused the to display the black screen and turn the PC in to an unresponsive machine, which then, requires a reboot to recover.
i subsequently used DDU to uninstall any/all drivers and let Windows 10 choose whatever it wanted. Whilst it installed the drivers correctly and asked to reboot, after it did it barely made it 1m30s without black screening and becoming unresponsive. So then, I tried my old Nvidia K600. Swapping out the Radeon VII sapphire directly for the Nvidia K600 and rebooting made the machine stable solid.
I also have a copy of MacOS Catalina installed on the same PC. The hackintosh install ran perfectly with Catalina 10.15.3 with an Nvidia K600 which worked smooth and natively with an OOB experience, no GPU kext or modification required. i then swapped it with the Radeon VII Sapphire, i could boot to desktop but again, I experienced constant black screens and unresponsiveness that required a hard reboot to recover. I then put the Nvidia K600 back in and the hackintosh worked perfectly again. I then put the Radeon back in and performed a clean install of MacOS Catalina 10.15.3 this time I was greeted with flickering screens, and a setup of two unusable screens. I unplugged one of the screens and image became stable... then a few minutes later the Hackintosh black screened and became unresponsive. This happened a few times, and the pattern of having two DP outputs connected resulted in flickering and unstable image on one screen and a blue box on another.
Now, the black screening isn’t just a black screen. It’s actually killing the output of the card and sending the display in to sleep mode. In fact, not only is killing the output to the display, it’s also ‘bricking’ the PC. If it was just the display that was turning off, I would still be able to RDP to my windows 10 1903 build from another terminal OR I would be able to screen share from another Mac. Neither OS found the PC to connect to which means the machine was not on the network or even in a working state. A quick scan of the home network proved that the Z620 had indeed vanished off the network - (Vanished meaning it was bricked, with power on and PC fans spinning).
So the direct correlation in this seems to be the Radeon card. Now, the card requires 300watts to function, my power supply is 800watts and the 2x6 pin supply is of 300watts. The 6-8pin connector is questionable as the wires don’t match HP proprietary connector. Once I receive the new HP 6-8 pin connector (£50 per adapter!!) I will know for sure whether it’s the Radeon VII Sapphire or whether it was the cheap eBay 6-8 pin adapter. Given that the cheap eBay adapter allowed the Radeon to boot to desktop means that there was enough power going to the Radeon VII at boot and the launch of desktop.. but the was quickly greeted with the dreaded black screen.
I will update soon to see if my theory was correct.
