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PPC7410 thermal adheasive?
Posted by: techknight on 2020-07-01 09:29:35
This isnt really mac related, but its the same CPU. I have a single board computer that once had a little snap clip heatsink that hugged the CPU itself, and the heatsink part screwed on. Kinda neat. But it broke....

Cant seem to find that thing anywhere, and I was wondering if anyone has any experience with the PPC7410 chip or know if a thermal glue/adhesive would work on this type of chip?

Posted by: LightBulbFun on 2020-07-01 10:24:53
what was the heatsink clip setup exactly? from what you describe it sounds a lot like the plastic square that Lombards and Pismos used, that would snap round the ceramic package of the CBGA360 CPU itself and then have 2 screw holes for a heatsink to screw into

perhaps one of these plastic squares could be used or adapted to replace the broken original setup? 🙂  

out of curiosity what SBC is it exactly? 🙂  

Posted by: techknight on 2020-07-01 10:26:06
Ill take a picture 

Posted by: techknight on 2020-07-01 11:07:29
Images: 

https://drive.google.com/file/d/1JKUke1wz27o2MYToJwM4LXDPUkAMBaHJ/view?usp=sharing

https://drive.google.com/file/d/1JKwlAp6ggnk8jqHcwTZQV6GlkpcFnpdQ/view?usp=sharing

https://drive.google.com/file/d/1JiQb2lT15D7bl7vUkYq6vYYJGxJSyJ0D/view?usp=sharing

https://drive.google.com/file/d/1JL8SQRhZE51wV_SM8KJiTXtb2gvBUWZ3/view?usp=sharing

https://drive.google.com/file/d/1JVOC8HhFKdVRMeu6q6Ax0mjmaTzAH7mN/view?usp=sharing

https://drive.google.com/file/d/1JNTmqkLwtupYaDrtIr9DBAjsg6ikduRe/view?usp=sharing

Thoughts? 

Posted by: switch998 on 2020-07-08 07:40:20
At work we use 3M 8810 for chips with bare dies like that. It will probably hold, but won't be great, even if you use strong thermal adhesive. Those screw type heatsinks aren't very common nowadays so you might be out of luck re-using the original parts.

In combination with the thermal tape, I'd recommend getting a more modern heatsink with integrated clip, something like this (or check enzotech, as an alternate vendor): https://www.radianheatsinks.com/ez-snap-clip/

Posted by: LightBulbFun on 2020-07-15 06:15:32
Images: 

https://drive.google.com/file/d/1JKUke1wz27o2MYToJwM4LXDPUkAMBaHJ/view?usp=sharing

https://drive.google.com/file/d/1JKwlAp6ggnk8jqHcwTZQV6GlkpcFnpdQ/view?usp=sharing

https://drive.google.com/file/d/1JiQb2lT15D7bl7vUkYq6vYYJGxJSyJ0D/view?usp=sharing

https://drive.google.com/file/d/1JL8SQRhZE51wV_SM8KJiTXtb2gvBUWZ3/view?usp=sharing

https://drive.google.com/file/d/1JVOC8HhFKdVRMeu6q6Ax0mjmaTzAH7mN/view?usp=sharing

https://drive.google.com/file/d/1JNTmqkLwtupYaDrtIr9DBAjsg6ikduRe/view?usp=sharing

Thoughts? 
interesting little setup!

if theres space perhaps look to see if a Pismo heatsink will fit, they work by having a little square plastic thing that clips onto the CPU package itself, then the heatsink is screwed onto that 🙂  

(might be worth buying an entire Pismo CPU card heatsink and all, as while I dont think finding the heatsink on its own would be too hard, finding the little clip on its own might be a bit tricky)

said plastic clip thingy is also shared with the Lombard but they have a much smaller heatsink

that being said, you could JUST use the plastic square clip thingy and screw into it your own (custom) heatsink

Posted by: techknight on 2020-07-15 11:37:24
the plastic square clip is whats broken on this card. 

Posted by: Franklinstein on 2020-07-20 17:00:34
Sadly bare flip-chip parts like these don't really have enough surface area for an adhesive to work effectively. The screw-type heatsinks were not ideal since the plastic retainer bits seem to like to break and aren't readily available as replacements. As noted, the PowerBook and early iMac processor cards had these similar plastic retainers for their thermal transfer discs but those were under far less stress than the screw-down heatsinks and I don't think they're compatible at all. You could, however, try to use one of these and then use thermal adhesive to attach a larger heat sink to the disc.

Posted by: techknight on 2020-07-21 00:31:18
I ended up getting jb weld, I used that to expoxy down the clip. then I got some arctic silver thermal adhesive for the heatsink itself so I could screw it down to the CPU. so its bonded between heatsink and CPU, and now its also bonded at the heatsink clip to PCB/CPU ceramic, 

So we will see... 

Posted by: johnklos on 2020-07-21 01:23:00
The Arctic Silver thermal adhesive is quite strong and shouldn't have any problem holding the heat sink and fan.

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