I actually did this mod for all of my S1s and saw a 1GH inprovement across each unit. I have enough for one unit coming in on Monday so I'll go ahead and try it myself to verify.
The part you are looking for are the eight grey square "blocks" above the heat sink. There were only four-per-blade on the S1
http://i.imgur.com/RkuPkLy.jpgThe layout of the S3 board seems to allow for a single long heat sink to cover all of the dc-dc converters? The S1 layout had caps in between preventing the use of a single large heat sink. I bet the larger surface area will work much better than the smaller individual heat sinks.
Anyone know where to find something that will fit, and how to properly attach?
This is a terrific idea. I can check our old stocks and find some perfectly straight/flat heat sinks from old server video cards. I have some dual-head Quadros in mind that I might be able to cut up easily.
Either way won't be able to test until Monday. My fiancée will kill me if I head back in this weekend.
Definitely not on call.
Anyone know a good source for 3M thermal adhesive strips?
Looking forward to seeing this with a stripe across the 8 of them.
Yes, this is great design if it works.
In S2 bitmain figured out to incorporate a steel plate in latest batch. I think that that steel plate helped in heat distribution as well (apart from structural integrity).
I doubt that they can incorporate such heat sink in their design at this stage, but who knows.
Edit: they (Bitmain) can probably use this at a minimal cost ($0.3/piece):
http://www.alibaba.com/product-detail/led-strip-aluminium-heat-sink_1996606714.html