I have a serious problem with my Radeon Pro Duo Polaris 32GB GPU. The card works only in VGA mode. After downloading and installing drivers from this site: Radeon™ Pro Duo (Polaris) Drivers & Support | AMD and restarting computer my OS is freezing on startup (in the moment when the four-color animated Windows 7 logo entitled "Starting Windows" appears on the screen)
After a few seconds the logo animation freezes and nothing more happens, windows doesn't start. I have to start the system in safe mode and remove the driver with DDU to be able to work in VGA mode.
I have already:
- checked the system with sfc/ scannow with a positive result ("Windows Resource Protection did not find any integrity violations")
- get rid of all previous AMD GPU drivers (i had a RX 580 previously)
- did a clean install of Windows (Win7, Ultimate, 64-bit)
- installed all the uptades available
I have also tried installing older AMD software (Radeon Pro Software Enterprise, Revision Number 17.Q2.1) and it didn't freeze Windows and it even worked (I tried Blender 2.79 GPU render) my my card was recognized as two radeon pro wx 7100 cards. But i guess it doesn't use its full resources, because 7100 has only 8 GB of VRAM.
What may be the cause and what should I do to get my Pro Duo working properly?
Because this may be useful for some other user i post the problem description and solution below.
The problem was power supply. I have a BeQuiet BQ-L8 700W PSU. It has two separate cables for powering PCI-E devices. Each of those two cables is splitted into two plugs. I connected those two plugs of one cable into both power supply sockets of my GPU. But it seems that my BeQuiet PSU has some kind of power/current/amperage limitation for each PCI-E wire. When the GPU chipset was launched (i mean all the stuff that is used for 3D acceleration, not the basic VGA circuits) along with Windows (at the end of displaying splash screen) it consumed more power that a single PCI-E wire from my PSU could handle and some kind of fuse was swithing off the power for that cable. Now i connected two separate PCI-E power cables to my Pro Duo GPU and everything works fine.