Question Why does GPU slow down during gameplay?

[daharding31]

Whenever I run any program that puts max load on my GPU for more than an hour or so the fps drops drastically and the speeds return to what appears to be idle. It seems almost as if the GPU forgets that I'm gaming.
My PC build consists of:
Ryzen 7 2700x
MSI x470 motherboard
MSI air boost vega 56 (undervolted, running vega 64 bios)
2 x8 Corsair vengeance pro ddr4 3000

 

[webworkings]

And what are the temps when this happens?

 

[daharding31]

And what are the temps when this happens?

Core is between 63 and 69
Hbm2 is ~ 77
And after doing some research about hotspot, I learned ~ 105 is the max for that but mine is at between 70 and 81

 

[daharding31]

Whenever I run any program that puts max load on my GPU for more than an hour or so the fps drops drastically and the speeds return to what appears to be idle. It seems almost as if the GPU forgets that I'm gaming.
My PC build consists of:
Ryzen 7 2700x
MSI x470 motherboard
MSI air boost vega 56 (undervolted, running vega 64 bios)
2 x8 Corsair vengeance pro ddr4 3000

Someone on Reddit recommended I look into thermal throttling which would add up if any of my temps were out of range

 

[rgd1101]

make and model of the psu?

 

[daharding31]

make and model of the psu?

Thermaltake tough power 850 rgb