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Toronto, Ontario, Canada

Recently I've been getting increasingly nervous about the SID chip in my breadbox C64 overheating.  Unlike the C128, there's no heatsink on the chip and it's known to run quite hot.

First, I'd like to know if it's really worth adding some sort of heat spreader to the chip or if I'm just being paranoid and secondly I'm wondering what your suggestions would be for doing so.  There's no easy way of screwing a heatsink in, so my solution would probably involve some sort of non-conductive clip attached to the IC socket.

I've seen only a couple of people online adding heatsinks to their C64s, so any links to addition resources would be welcome.

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Brunswick, GA USA

There already is a heat spreader in a breadbox C64, a sheet of aluminum between the pcb and the keyboard.

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Toronto, Ontario, Canada
chunter wrote:

There already is a heat spreader in a breadbox C64, a sheet of aluminum between the pcb and the keyboard.

None of my breadbox C64s have any proper heat spreaders.  They have these awful aluminum-covered cardboard inserts that do nothing for heat dissipation (and I'm skeptical as to whether they do much for EMI reduction either).

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Rochester, NY
chunter wrote:

There already is a heat spreader in a breadbox C64, a sheet of aluminum between the pcb and the keyboard.

not on a breadbox C64, unless maybe it's one of the late models before they switched to the new case. most classic 'breadbox' C64s have the cardboard/foil shield over the PCB, which actually traps heat in. better to remove this if yours has it. late model and (all?) 64c (new case) models have the metal shield/heat sink in them.

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Toronto, Ontario, Canada
jbuonacc wrote:
chunter wrote:

There already is a heat spreader in a breadbox C64, a sheet of aluminum between the pcb and the keyboard.

not on a breadbox C64, unless maybe it's one of the late models before they switched to the new case. most classic 'breadbox' C64s have the cardboard/foil shield over the PCB, which actually traps heat in. better to remove this if yours has it. late model and (all?) 64c (new case) models have the metal shield/heat sink in them.

Well then, based on the fact that Commodore themselves added heatsinks to later models, I think that answers my question as to whether it's worthwhile.

^__^

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Brunswick, GA USA

The ones I took apart had silicone gunk on the ICs, attaching them to the spreader. Could the previous owner have done that on purpose? Fwiw I took the sheets out because they were messy...

I had to test the ICs in four models to combine them into two that function (maybe, they are stored now and I have no way to test them.)

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New York City

Totally unnecessary, but if you are paranoid put a video card heatsink on it. It might not fit on the computer then, though. Be careful about such space restrictions.

Silicone gunk comes de-facto on those computers with metal shields.
The cardboard shit appearing in later C64C models makes it evident that a heatsink is not needed as that cardboard does fuck all to dissipate heat. (No, not all C64Cs have metal shielding, I actually am yet to see one which has that, all the metal shields I've seen were in breadboxes)

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Toronto, Ontario, Canada

I've already cut a hole in the cardboard/foil above the SID chip and I've disabled the joy ports to prevent the SID getting killed that way.  Guess I'll leave it at that for now.

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New York City

POTY and POTX signals will NOT kill the SID, you are much better off  eliminating the EXT IN signal for that

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Rochester, NY
akira^8GB wrote:

(No, not all C64Cs have metal shielding, I actually am yet to see one which has that, all the metal shields I've seen were in breadboxes)

well, then you must not be talking about ones sold in the US.

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Toronto, Ontario, Canada
akira^8GB wrote:

POTY and POTX signals will NOT kill the SID, you are much better off  eliminating the EXT IN signal for that

Yeah, did so.  I also grounded it to get rid of the noise, though I may get around to a feedback mod at some point.

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Brunswick, GA USA
jefftheworld wrote:

Yeah, did so.  I also grounded it to get rid of the noise, though I may get around to a feedback mod at some point.

Bucket delay?