Question ASUS RX580 Strix dropping to 300mhz when hits 80c

[jkrm]

Hello! I have a problem with my ASUS RX580 Strix 8GB. On stress test, when the gpu hits 80c it drops the core clock to 300mhz for about a sec, and keeps repeating this... But only drops when hit 80c.. and it happens only when I set the power target to max (+50%)

I recently replaced the thermal paste with Thermal Grizzly Hydronaut.

In this picture you can see the strange behavior

https://imgur.com/IGdLwiD

View: https://imgur.com/IGdLwiD


Power target is on max (+50%) when the dropping occurs, when the line is flat again is when the power target is on stock.

Everything is updated (bios, drivers, windows, etc)

I don't think is thermal throttling because 80c is not that bad... What do you guys think that can be?

Setup:
Ryzen 5 3600x + h100i v2
HyperX Fury 3000mhz cl15 8gb x2
Asus X370-F Strix
Corsair CX550M
DeepCool macube 310 (Not a lot airflow, but it's a 3 fan GPU and I have 3 exhaust fans + 2 h100i intakes)

 

[jkrm]

https://imgur.com/K0gXurk

View: https://imgur.com/K0gXurk


Look at the afterburner... It's showing the mhz of the GPU, very strange behavior!