Recently i have bought two Sapphire RX470 Nitro+ 4GB videocards to use them in crossfire. I previously had two ASUS HD7950 Top V2 videocards in my system running in crossfire and had 0 issues with them.
Asus z77 sabertooth (with latest bios ver);
16GB Hynix RAM;
win10 x64 pro (with all latest updates);
Ok, so i have installed both videocards in system, started my pc and downloaded latest amd crimson driver (16.9.2). But when setup is trying to install driver for the second adapter, display goes blank and remains the same until i restart my pc. So, i entered safe mode, deleted amd driver with display driver uninstaller and restart pc to try install driver for the second time. But result was the same: display goes blank as soon as setup try to install driver for a second adapter. So, i`ve decided to swap videocards by places and see, maybe this will help. But result was the same.
What i did next is i removed one videocard and tried to install display driver. It works! Then i again changed videocard to another and it worked again. So i started to think, that maybe i have a problem with second (lower) pci-e slot. But when i installed videocard in it, i get it working.
So to summarize at this point:
both display adapters is working if only one installed in PC
both pcie slots are working
I start to think, that maybe the problem lies in my PC configuration, so i moved two videocards to another home PC (i7-4770k, 16GB crucial ballistix ram, Msi-z87-gd65-gaming, 800W PSU, win10 x64 enterprise with all the latest updates, no overclock), but result was the same - can`t install driver for a second adapter.
Interesting thing, that if i clean drivers with display driver uninstaller, my two videocards are showing in device manager, but one of them (the one which lower) is always has some triangle icon with an exclamation mark. And when i click on its properties i get this error inside:
"This device is not working properly because Windows cannot load the drivers required for this device. (Code 31). The driver trying to start is not the same as the driver for the POSTed display adapter."
I have the same error on both PC`s.
What i tried:
Test videocards one by one. Result: each adapter is working.
Test videocards in both pci-e slots. Result: each adapter is working in every pci-e slot;
Change bios setting: disable fast boot, play with pcie speed settings (gen1, gen2, gen3, auto). Result: these changes not help
Try to manually install drivers. Result: bsod or blank display if i try to install driver for adapter with exclamation sign in device manager
Try to install different drivers: 16.8.3, 16.9.1, 16.9.2. Result: same - display goes blank while driver installation or i get bsod with something related to atikmpag.sys (or atikmdag.sys).
So my question is: why second adapter always have problems with driver installation and why it has excalamation mark in device manager? How to solve this issue?
Thanks in advance!
PS I`m not the single with this issue:
Any help will be appreciated!
Edit. Problem solved by clean Windows installation.