I've found processors in the 30-40W range can heat up heatsinks to the point they can be burning to the touch. Heck, I've even had 486 processors that can warm up a heatsink to the point of it feeling quite hot.

Looking up the specs on that processor it's got a TDP of 30W. So with a flimsy heat sink and good heat transfer, it wouldn't surprise me that it gets quite hot.

Best bet would be to jerry-rig a fan for added cooling.

I second a fan, I had a mishap of forgetting to put the fan back on my mom's win ME athlon computer. It got so hot while running DOS that the heatsink popped of with an audible "BANG!" since the retaining clip warped from the heat. It was still scalding hot to the touch 10 minutes later. Older CPUs can get incredibly hot.

If this CPU/heat sink came, for example, from a Dell system, Dell had a 'shroud' enveloping the Slot 1 package and heat sink and directing airflow towards a rear case fan. I don't think slot 1 CPUs are supposed to be passively-cooled...

https://www.theregister.com/1999/04/28/550mhz … as_overheating/

Errius wrote on 2024-05-30, 00:15:

https://www.theregister.com/1999/04/28/550mhz … as_overheating/

1999, and they are calling Intel "Chipzilla". Hahaha, that rag has been a mainstay for such a long time 😀

VivienM wrote on 2024-05-29, 23:56:

If this CPU/heat sink came, for example, from a Dell system, Dell had a 'shroud' enveloping the Slot 1 package and heat sink and directing airflow towards a rear case fan. I don't think slot 1 CPUs are supposed to be passively-cooled...

Exactly this. That heatsink with the up down bent plate fins looks exactly like it comes out of a GX1 dell, which cooled it with a shroud covering it and an extractor fan. Just stick a fan on top of it, it is not supposed to run without one.

I acquired one of these with a HP workstation, and yes, there is a duct over the CPU that pulls air over it and out the back of the case. Overheating is not a problem unless the case fan fails.

ETA: Here is what I did when I moved this motherboard to another case that didn't have such a duct system

douglasfir wrote on 2024-05-29, 23:20:

I recently built a Pentium 3 system, I installed a P3 550 CPU, the original was a Celeron, the 550 has a much less significant heatsink, very thin aluminum vanes. No fan, the celeron had a fan and a decent sized heatsink and ran cool, the 550 runs HOT, touching it for more than half a second would burn you. I stopped running the machine when I discovered this. It is not overclocked, settings are default. Is this normal? if so, are there aftermarket heatsinks available? I have a hard time believing this is the normal operating temperature (which is at idle by the way). Can anyone help?

Heatsink cooling is about surface area and airflow. You've got a good-looking heatsink (thin aluminum is not bad), but nothing to move the hot air off of it. Just put a fan on it (or place one near it so that the airflow is directional to the fins) so that the heat can transfer from the metal, and the heatsink has a chance to cool. The fact that it's getting hot means it's conducting heat well, which is a good thing.

Also, if you're using Windows 95 or -98, you need to run a background application to cool the CPU, such as Rain. These operating systems don't know how to halt the CPU when it isn't being used, so they're not idle even when they're idle, if you can dig it.

douglasfir wrote on 2024-05-29, 23:20:

I recently built a Pentium 3 system, I installed a P3 550 CPU, the original was a Celeron, the 550 has a much less significant heatsink, very thin aluminum vanes. No fan, the celeron had a fan and a decent sized heatsink and ran cool, the 550 runs HOT, touching it for more than half a second would burn you. I stopped running the machine when I discovered this. It is not overclocked, settings are default. Is this normal? if so, are there aftermarket heatsinks available? I have a hard time believing this is the normal operating temperature (which is at idle by the way). Can anyone help?

Those processors need air flowing over/through the heatsink, you can't leave them completely passively cooled. If it doesn't have a fan already attached to it, that means it's originally from a PC that had a fan duct system as part of the case.

I have a P3-600 with a large heatsink and it gets burning hot without air through it, I fixed the issue by bolting a cooling fan to it.

Here's a pic:

That CPU came supplied in a system that had a fan drawing air over it.
It used the Case fan and the PSU fan for its air flow, it is passive in that it doesnt have an integrated fan on it but it can not dissipate the heat of a 550 without air flow.

For what it's worth, I have a retail box version of the P3 550 and I've never noticed a heat issue when I ran it (albeit, the retail shroud makes it so you can only touch the outside aluminium and none of the central fins).

VivienM wrote on 2024-05-29, 23:56:

If this CPU/heat sink came, for example, from a Dell system, Dell had a 'shroud' enveloping the Slot 1 package and heat sink and directing airflow towards a rear case fan. I don't think slot 1 CPUs are supposed to be passively-cooled...

That makes a lot of sense and probably the setup this processor was designed for.