Hi, 
Can you please give me some advice, I'm heaving trouble with new Sapphire RX VEGA 64 Cards.
I had two cards running before on my motherboard:
1. slot PCIe 16x - GTX760 (working)
2. slot PCIe 16x - RX470 (working)
Changed to 2x VEGA 64 cards:
1. slot PCIe 16x - VEGA 64 (working)
2. slot PCIe 16x - VEGA 64 (not detected fans not spinning - overheating)
Tested and plugged old cards back as it was and 2. slot does not work anymore:
1. slot PCIe 16x - GTX760 (working)
2. slot PCIe 16x - RX470 (not detected fans not spinning)
Tested only one card on 2.slot:
1. slot PCIe 16x - Removed no card
2. slot PCIe 16x - VEGA 64 (1 long beep and 3 short beeps)
Tested only one card on 3.slot:
1. slot PCIe 16x - Removed no card
2. slot PCIe 16x - Removed no card
3. slot PCIe 16x - VEGA 64 (1 long beep and 3 short beeps)
Conclusion:
1. PCIe 16x slots are not the problem (not broken or dusty)
2. All cards are working but only in 1. PCIe 16x slot
So far:
1. Uninstalled drivers with DDU about 4 times
2. Installed and tested with different AMD drivers 17.xx - 18.2.1
3. Updated Motherboard BIOS
Still does not work! Please help!
Motherboard: ASUS P9X79 https://www.asus.com/Motherboards/P9X79/
PSU: CROSSAIR RM850 - 850W
