Strong thermal tape or epoxy?
- Thread starter Cyber-Mav
- Start date
Soldato
- Joined
- 30 Jul 2012
- Posts
- 2,774
With those stickle brick looking ram sinks I left the thermal tape on them and put them in place as normal, then added a teeny tiny dab of silicone sealant at two opposite corners. *NOT* under the sink mind, it was just to bridge the sides/edge of the sink to the circuit board of the card once the sink was in place, so you get full contact of the sink to chip, and the ligament of sealant on the side will just hold it. It was like a really small dab of the stuff applied with a cocktail stick so it could easily be removed when you need to take the sinks off again. Once set the sink will not be able to fall off.
thats mega expensive, was hoping for a cheapo solution
Last edited:
doesnt silicone sealant melt off at relative low temps like 70c?
What sort is it you use? Standard bathroom dow corning?
Its not a pu adhesive is it like tiger seal? Thats stuff almost permanent
Last edited:
It was a small tube of that transparent silicone what smells of vinegar, got from RS components if I recall, but really anything which will set and provide a bit of extra mechanical support against gravity wanting to defeat the sinks adhesive. Also, with it being rubber effectively, it will flex with thermal expansion, unlike if you tried to do the same thing with small dab of hard glue or cement. And to be extra clear, I am talking about using this on the sides of the sink to make a very small ligament to the circuit board in a couple of places, opposite corners is the most sensible. All it is doing is basically stopping them wanting to fall off if the sink adhesive goes off or something. When it comes to taking the sink off it will just pull off as normal, and then you would need to carefully tear off any of the sealant on the circuit board. The amount needed should be so small that it should come off without any bother. Maybe test the process on an old card if you have anything lying about.
Man of Honour
You have to thoroughly clean the ram and VRM chips with IPA first. Any residue or lint and they will eventually fall off. I always used Akasa's excellent thermal tape and never had a single heatsink fall off.
I wouldn't use epoxy because once it's on it's never coming off which could be a problem at resale time.
I wouldn't use epoxy because once it's on it's never coming off which could be a problem at resale time.
You could perhaps use RTV gasket maker. It's a high temperature silicone used for making gaskets on engine blocks, it'll take the temperature of ram, I think it's good for well past 200c.
Edit: This is if you're doing a thermal paste under the ramsink and then silicone at the edge kind of deal.
Last edited:
No, you're correct, it wont do thermal transfer, but I thought you and @Bubo weren't talking about using it like that.
He seems to be recommending using the stock thermal tape to attach the ramsinks, and then using a dab of silicone on an outside edge to add extra mechanical support, which lead into talk of whether silicone could take the heat, hence I suggested RTV. So there is no RTV between the ramsink and the IC, only on an outside edge to help anchor it.
i see, can use heatsink with regular thermal paste then use the sealant on the edges to bond heatsink to pcb. didnt think sealant like this would be reliable with heat but worth a try i guess. would hot glue gun work? not sure what temp the glue melts at, higher than 100c i would have thought?
I'm not sure using thermal paste instead of thermal tape in this scenario is a good idea to be honest. The adhesive tape is doing the majority of the bonding work here, the little bit of sealant is just adding some extra support. I guess it might work but there since there is no pressure acting to press the sink to the board it could fall away from the card slightly unless you add a lot more of the sealant than I would recommend to keep it "pressed" down, or "pressed up" in actual fact. Not sure how that would affect the thermal performance, but maybe sine it is actual thermal paste it could be more thermally effective. Maybe a case for another test. But the more you add the harder it will be to clean up when you need to remove them to refit the original cooler.