Quote Originally Posted by dnottis View Post
Control chip of VRM part, VT1165MF, U601 on the PCB - needs a heatsink too as per ATI.

if "ATI" says VT1165MF needs sinking, then why not cooling it with the stock heatsink? Further contradicting this information, the VT1165MF receives no air flow whatsoever from the stock fan because the step that reaches the VRM's completely blocks any airflow across the entire width of the heatsink.

Either your contact at ATI is not in the thermal/mechanical group, or he is and he disagrees with the reference design, or he is simply mistaken, or you might have misunderstood.