Jasen Betts wrote in a message to Wayne Chirnside:

 JB> there was some sort of rubbery heatsink compound used  on the video
 JB> chip (I think) in Commodore 64s (or possinly some other home
 JB> compputer of that era) it looked like white silicone caulk.

All of the ones I ever saw (and that was a LOT!) used regular pasty
heatsink compound...

The earlier ones had the video chip in a little metal box,  the later ones
didn't but relied on the "sheild" over the board to conduct heat
away from the chips.

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