I was thinking about that, with the TMD fan not having a motor body in the center, it focus's air to the center of the heatsink. To share what I was thinking, if you can find an adapter that tapers in with a slight cone effect, then it will focus the air in the center of the heatsink, and the location of the motor body shouldn't be a problem, but you'd need at least a minimum of 1/2 an inch between the fan bottom and the heatsink top, to raise the fan motor away from the heatsink far enough so it wouldn't block the air flow. Then theres the weight factor, the Aeroflow is not a lightweight heatsink, even though you'd be removing the existing fan, what you're considering adding is about twice the weight you're removing, because you'd definitely want to add a fan guard to the top of it.
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