I have 2 setups with Vega 64(Strix and Gigabyte) The Strixx runs flawless even though its hotter(due to the awful VRM). However, on the Gigabyte model when launching a game or even Heaven Unigine, I'm getting a black screen and fans revving up. Running the Strix with a Corsair VS650 PSU and the Gigabyte with at FSP K 700W. Both PSU are almost 1 year old.
After swapping the GPUs, the issue was still persisting on the Gigabyte Vega 64. After checking the 1st PC I noticed that the 2nd 8 PIN PCI-E extension was melted. Cleaned the 8-PIN slot on the Gigabyte GPU, hooked it up on the 2nd PC and it melted it again.
Is this a PSU issue? Take note that I did test the Gigabyte 64 on 2 separate rigs that has their own PSU