Light DIY on my 1240 accelerator

[mikeymike]

I mentioned a while back (on which thread I'm not sure) that the heatsink/fan had come off of the CPU on my 1240 accelerator card.  I believe a hot glue gun was advised as part of the solution.  I checked the temperature that it works on, it brings the glue up to at least 120C, so I seriously doubt that the processor is going to do the same, unless the processor is planning on melting too

My plan is to use a bit of thermal compound that I have for x86 CPUs on the centre underside of the HSF, give it a small bit of squelching around on the CPU, bearing in mind that it has to be in a particular position in order to fit in the trapdoor, then use the hot glue gun I recently bought to place blobs on three out of four sides (I believe one side would be sticking to the RAM if I did that) of the HSF.

Thoughts?

I suppose one other precaution I should take is to use a pencil to mark the boundaries of the ideal position of the HSF.

[mikeymike]

I intend to have the trapdoor closed (it's the trapdoor sent with the 1240, so it has a hole for the fan to blow air through), so wouldn't that provide the pressure you describe?

People have said that a glue gun for this job is a bad idea, but haven't said why, apart from the point about applying pressure, which hopefully is addressed by the custom trapdoor (which doesn't expose the whole HSF, just the fan).

[mikeymike]

I think people's main concern is the initial thought that the glue is being used *between* the CPU and heatsink

Er, no

I planned to put a small bit of thermal compound (I was thinking about the size of a cooked grain of rice) in the centre underside of the HSF, then put it in the right place, then use the hot glue gun to put small blobs on each corner of the HSF, not so much that it goes under the HSF but beside it and on the CPU.

A couple of pics of the accelerator card:
http://lorien.legolas.com/040%20HSF%20off.jpg
http://lorien.legolas.com/040%20HSF%20on.jpg

Re: heat from 68040 - the HSF gets hand-hot after cooling the processor for a while (half an hour?).  I would guess its temp as 40 - 50C.

[mikeymike]

Would this do the trick?:

http://www.cclonline.com/product-info.asp?product_id=15295&tid=gsearch