SILVERSTONE RVX01BR-WThe card should not throttle down when the TEMP reaches 80 C. Which PSU do you have ? List full PC specs as well. Try to make a custom FAN profile via the MSI Afterburner tool.
Using Bitfenix Led fans. 4 intake Bitfenix Spectre Led ( 3 at bottom and 1 on front putting air directly on graphic card ) and a Bitfenix Spectre Led PWM in the top ( with corsair H60 ).Do you have Three 120mm Air Penetrator fans included for sublime vertical air cooling? Do you have a front Fan? Is the H60 radiator on the back or top?
86F in the room, but i think there is some temperature limit set somewhere. I also have a Sapphire RX580 Nitro+ that reaches 83/84C degrees, but without presenting this problem.From Silverstones web site it sounds like they want the case air flow to come in the bottom and out the top. Old school was in the bottom front and out the top back. Hard to Say how good the air is moving without doing a smoke test. What is your room temp? I have been having to run my window unit on 66F for 72F in my bedroom , heat index been running 105F here.