How to Silence a Radeon HD 4870 or 4890

Disassembling the original heatsink

Put the card on a working bench, its back side towards you, and remove the 14 screws, starting with those pointed by green arrows. Then remove the "blue" ones which are fixing the heatsink to the CPU. Remove them slowly and slide them slightly while pulling them out in order to prevent physical stress and tension on the GPU. When re-installing them later on, one will have to screws them back slowly, in turn and in diagonal.

Then once the GPU is unveiled, clean it well to remove any remaining debris of thermal paste with a soft tissue. Be careful not to drop thermal paste residues on the capacitors located around the GPU, as it could create short-circuit. You can carefully vacuum clean the area when you are done.

Here starts the changes when compared to the default procedure. We will use the base part of the original heatsink to cool down memory chips and the voltage regulator module (VRM).

Carefully remove the screws without damaging the thermal pads, we will then be ready to assemble the new heatsink.