This particular model as well as some of the Others in this line up choose to omit a heatsink on the IC that controls the Fans. The Temp on that Chip controls the fans as well. When a certain temp is met it ramps the fans to 100%. Even when directly writing to the addresses on the IC it overrides it to whatever it wants when it wants. It's a baked in function that cannot be disabled afaik. The solution is to get cooling to it. You can either scrap off part of the heatsink coating and epoxy a short heatpipe bent to shape or use adhere a copper shim to bridge to the heatsink. a tiny heatsink added to the die will not work unless you have a fan pointed at it. I ended up using KPx, a copper Shim, some heat pads and thermal adhesive on mine to mostly solve the issue. it still occasionally hits that threshold.