It would be nice to have some way to measure the temperature, but I would guess that the temperature would have been somewhere between 50-60C since I was only able to hold my finger there for few seconds.

Skyscraper wrote:

Some Intel DX33 CPUs seem to run hotter than others, one of the two extra I tested even locked up after 10-15 minuts or so at 40 MHz looping PCP bench.

The AMD DX40 (could not find an AMD DX33 eventhough I should have a few) was running like champ at 40 Mhz without heatsink looping PCP bench. It did get pretty hot but after I ended the test 20 minuts or so in the probe showed about 40 degrees but when pressing my thumb aginst the middle of the CPU I would say 50 degrees C is a better estimate.

This is why i just swap one fan, or heatsink + fan, and i will just not give a f**k about what is happen inside the case or temperatures.. As seems some people forget now is winter, and the temperature is under subzero, some days even -10, -15c, and in the hot summer they guy that did make the temperature test, will get +20c on top of now, or more depend on the temperature.....

Skyscraper wrote:

Some Intel DX33 CPUs seem to run hotter than others, one of the two extra I tested even locked up after 10-15 minuts or so at 40 MHz looping PCP bench.

Yes, but a 33->40 MHz overclock is quite significant, especially without any cooling whatsoever.
I take it all CPUs ran fine at 33 MHz?

Anyway, I hope we will never have to hear again that these CPus 'need a heatsink' (let alone a fan), they clearly don't. In fact, I'm surprised that even the DX50 doesn't need one. I thought the DX33 was the last one that was usually without a heatsink.
Anyway, if people want to put heatsinks and fans on their CPUs, that's up to them... Just don't go around spreading misinformation about CPUs 'needing' heatsinks and fans, when they clearly don't.

I never said it needs it. Only that there might be some advantages for having some cooling.
Same as voodoo 3 cards don't need a fan and have been designed to have only passive heatsink.

Still there are couple of brands that says you need to add heatsink and fan, no matter the intel ones does not have that thing on them

Baoran wrote:

I never said it needs it. Only that there might be some advantages for having some cooling.
Same as voodoo 3 cards don't need a fan and have been designed to have only passive heatsink.

Every single Voodoo need upgrade of the existing heatsink, and even a fan, as they run hot as stoves, and pay attention even on idle..........

Yes, but a 33->40 MHz overclock is quite significant

That depends. For AMD chips it's next to nothing due to a smaller lithography.

I ran an Intel DX2-66 in my old packard bell in the mid to late 90s at 80mhz and never had a heatsink or fan on it. Though I do remember it had a fingerprint on the ceramic where I stupidly touched it once after it had been on for several hours. BTW...I had it that way for at least 3 years before I gave that system to my aunt. She used it until the early 2000s and only then did the CPU finally die. So it ran for nearly a decade at that speed with any active or passive cooling on it and likely finally died because my aunt was a heavy smoker and I am not. It was pretty crusty in there after it died on her and I came to fix it and said forget it and told her she needed a replacement at that point.

Scali wrote:

For example, the Space Shuttle uses original Intel 8088 CPUs. They've been to the moon and back many times (talk about thermal stress), and still work fine, 40 years later.

Space Shuttle hasn't been flown since 2011 now and I'm pretty sure they never went to the Moon in one 😜

keropi wrote:

I am almost certain that the Zenith 486/66 I had back then did not have a heatsink...
Nowdays for piece of mind I but heatsinks even on 286 cpus as they get too hot for my taste. Is cooling needed? Doubt it since those machines work after decades but nowdays a piece of thermal tape and a heatsink are very cheap and easily found so why not? 🤣 🤣 🤣

Actually I had a couple of 286 motherboards that came with special socket covers which hold a tiny heatsink in place 😁

Half-Saint wrote:

Space Shuttle hasn't been flown since 2011

Not sure how that's relevant.

Half-Saint wrote:

and I'm pretty sure they never went to the Moon in one 😜

Correct... They've not actually been to the moon, but they have been in space, and did re-entry many times. So the point about thermal stress stands, regardless.

Scali wrote:

but they have been in space, and did re-entry many times. So the point about thermal stress stands, regardless.

No, because the inside of the Space Shuttle didn't get hot and cold all the time, not even when re-entering earth, as that's what the heat shield was for. All crucial systems were temperature-controlled and the components had probably less thermal stress than any office PC on earth... They were built to still work when the temperature controll failed, however.

derSammler wrote:

They were built to still work when the temperature controll failed, however.

And fail they did: https://en.wikipedia.org/wiki/STS-1#Mission_anomalies

Half-Saint wrote:

Space Shuttle hasn't been flown since 2011 now and I'm pretty sure they never went to the Moon in one :P […]
Show full quote

Scali wrote:

For example, the Space Shuttle uses original Intel 8088 CPUs. They've been to the moon and back many times (talk about thermal stress), and still work fine, 40 years later.

Space Shuttle hasn't been flown since 2011 now and I'm pretty sure they never went to the Moon in one 😜

keropi wrote:

I am almost certain that the Zenith 486/66 I had back then did not have a heatsink...
Nowdays for piece of mind I but heatsinks even on 286 cpus as they get too hot for my taste. Is cooling needed? Doubt it since those machines work after decades but nowdays a piece of thermal tape and a heatsink are very cheap and easily found so why not? 🤣 🤣 🤣

Actually I had a couple of 286 motherboards that came with special socket covers which hold a tiny heatsink in place 😁

Something like this?

Picture of my 286 motherboad with the original heatsink. Got it for free and doesn't work because of too much corrosion, but I still had the picture.

Baoran wrote:

Something like this?

I used to have a 286 with this kind of cooler back in the early-mid '90s. (I know I was late, it was all I could afford.)

It also had a 287 and I'm quite sure the FPU could have used a heat sink too.

Now I see that 286 chips can run pretty hot too. When I tested my plastic LCC ones I found that Harris 16-25 and AMD 16MHz pieces are the exceptions, they were much cooler, more like lukewarm. They were probably made on a newer process.

Scali wrote:

Just look at the heatsink they put on the 486DX2-66... Just a tiny heatsink, no fan required. And that one was 6W.

Not to mention far from ideal thermal dissipation between heatsink and CPU.