Mosfet cooler by Thermalright

[grudgelord]

As promised, here are some images that I hope will explain the fit issues a bit more clearly. I apologize for the lousy quality. My camera is a POS and I refuse to spend more money on a new camera until I can afford a D-50 or D-200. My current system build has become a great cashsink so it's not likely to happen any time soon.

After the removal of the stock aluminum heatsink (along with the Northbridge and heatpipe assembly) you can see the MOSfets arranged in pairs.




Here is an HR-09U with the small sink centered on the Mosfets. While the sink contacts all of the MOSfets in this configuration they are only partially covered. I suspect that this might be adequate enough for cooling purposes but I still find it troubling. When spending $20.00 on a replacement sink I expect complete coverage of heat generating components.




Here's the heatsink, in the same configuration but shifted to the left in order to cover the leftmost pair. As you can see, this leaves the right completely out of contact with the foot of the sink.




And again shifted to cover the rightmost transistors. Once again, same issue with the left side.




Flipping the heatsink assembly offers no joy either as the row of MOSfets is boxed in by the presence of a capacitor at one end and the four pin power plug at the other, making it impossible to place the heatsink in this configuration as the "foot" prevents it from sitting in the space.




Enter the Dremel: By this time I'd become pretty annoyed so I measured the length of the stock sink (74mm) and trimmed a few millimeters from the foot of an HR-09S in order to get it to fit in the space, yet entirely cover the transistors. (Pay no attention to the ugly, blurry thumb or the pile of crap on my desk. Vandal elves invaded my home and made a mess of my desk while watching :banana::banana::banana::banana:.)




After trimming the heatsink now fits within the space and properly covers the MOSfets. The only drawback is that there's still not enough space to use the clips so I'll either have to use the adhesive pad that came with the heatsink or use a mixture of AS5 and Arctic Silver adhesive (the latter is my choice and the adhesive is en route).




I do wish the image quality were better so that you could really appreciate the problems of fit. It is difficult to get a good idea of the problem from these pictures but, unfortunately, the little camera I have doesn't like closeups in poor light.

My advice to anyone considering these sinks is to consider their measurements carefully. As long as either 57.5 mm x 12 mm or 80 mm x 12 mm will suit your needs then all should be fine (the stock heatsink measures 74 mm x 12.5 mm). The distance from the outer edge of the farthest spaced MOSfets is 72 mm, so that should be considered. All measurements were taken with calipers, albeit cheap calipers.

Of course, if you aren't afraid of a little modification (which I am not and I happen to enjoy it) then it shouldn't be a real problem. But it is a shame that modification is necessary for a proper fit on a part that has been stated to fit. I guess that's the sacrifice Thermaright had to make in order to create an item that could accommodate a wider range of boards.