Fan speed frame throttling issue

[Noremacecir]

I was playing pubg when i realized my temps were a little above my comfort zone (around 75 to 78) on an RTX 2080 which has a max of around 88 if i remember correctly. So i upped my fan speed with afterburner's auto fan speed tool and it sits at 80% speed or a little under mid game and keeps my 2080 at a nice 65 to 67 but i noticed about every 10 minutes my frames would suddenly drop to around 30 and keep spazzing out for 10 seconds before returning to the normal 90 to 120 i normally get.  This dropping would never occur before tweaking my fan speed.  Is there any chance running afterburner in the background or having the fan speed so high could be tricking my computer into thinking the temps are high enough to start thermal throttling or something along those lines?  Please leave your suggestions and i will troubleshoot further when i get the chance.