Naekyr

Hi I have this AIO: https://www.thermaltake.com/products-model.aspx?id=C_00003122 My CPU is getting very hot at 90c I can see in BIOS the pump is always running at 1800rpm. I also used HWInfo software in windows and even when stress testing the CPU at 100% load, the pump is always at 1800rpm The product is advertised as 3600rpm How do I make it work at 3600rpm so my CPU doesn't get to 90c??