Deksor wrote:

I've got a 400MHz pentium 2 that is fanless. I even managed to overclock it at 450 without adding anything and I don't have any problems with stability with that cpu. I also have a 350 MHz pentium 2 from Compaq wich has a very tall aluminium heatsink

Compaq Deskpro EN/EP with any slot 1 CPUs i think always had a big heatsink only, but cooled from the chassis fan. Very quiet systems.

Rawit wrote:

It sounds like I have plenty of options. I assume that in most cases a case fan is present? My current system is completely fanless, which is kinda neat and what I want for the new build, if possible. I'm going to compare and read about all of your suggestions.

Yes I had a case fan in my system, but way's to eliminate noise

Get a modern 3 pin fan and a fan speed controller for a 5 1/4 bay. Put the fan in the case with rubber grommets, also use rubber grommets to secure the disk drives and optical drives.

Scraphoarder wrote:

Compaq Deskpro EN/EP with any slot 1 CPUs i think always had a big heatsink only, but cooled from the chassis fan. Very quiet systems.

I have a EP with a Slot 1 Coppermine Pentium3 600MHz and it's passive. The only fan on the whole system is the PSU fan. Replacing the HDD with a CF card makes it practically silent.

PS: For some time I had an IBM PC300GL which had a Pentium MMX 200MHz with a passive heatsink and the only fan on that one was also the PSU fan. Even with 100% CPU load for long periods of time it was rock solid.

Would something like this be enough for anything socket 7 then?

http://www.ebay.com/itm/391229723676

James-F wrote:

If noise is the main reason for running fanless, HDD is one of biggest noise makers.
Go Solidstate or SD card IDE controller for totally silent system (and much faster).

I'm using a Compact Flash with an IDE adapter. The thing is completely silent and extremely fast, but I do miss the HDD noise: it was a reminder that the computer was indeed working and just didn't hang in the middle of a process. The HDD light doesn't do the job imo, as you have to look at it. I do wonder if there are mods to bring back some sound from silent drives, like putting a speaker on the LED path or something.

The one that was cooling the P200MMX I mentioned was a bit bigger, but that one probably has more (and thinner) fins, so it's hard to compare. For something up to Pentium 133MHz it's almost certainly enough though.

If you want HDD noise, just add an HDD 😉

jarreboum wrote:

Would something like this be enough for anything socket 7 then? […]
Show full quote

Would something like this be enough for anything socket 7 then?

http://www.ebay.com/itm/391229723676

James-F wrote:

If noise is the main reason for running fanless, HDD is one of biggest noise makers.
Go Solidstate or SD card IDE controller for totally silent system (and much faster).

I'm using a Compact Flash with an IDE adapter. The thing is completely silent and extremely fast, but I do miss the HDD noise: it was a reminder that the computer was indeed working and just didn't hang in the middle of a process. The HDD light doesn't do the job imo, as you have to look at it. I do wonder if there are mods to bring back some sound from silent drives, like putting a speaker on the LED path or something.

Not even close. Fully passive CPU heatsinks for socket 7 CPUs are two-tree times bigger. I'd use something like this to pe on the safe side:
http://www.hsmz.eu/sites/hsmz.eu/files/imagec … ges/103157.jpeg

jarreboum wrote:

Would something like this be enough for anything socket 7 then? […]
Show full quote

Would something like this be enough for anything socket 7 then?

http://www.ebay.com/itm/391229723676

James-F wrote:

If noise is the main reason for running fanless, HDD is one of biggest noise makers.
Go Solidstate or SD card IDE controller for totally silent system (and much faster).

I'm using a Compact Flash with an IDE adapter. The thing is completely silent and extremely fast, but I do miss the HDD noise: it was a reminder that the computer was indeed working and just didn't hang in the middle of a process. The HDD light doesn't do the job imo, as you have to look at it. I do wonder if there are mods to bring back some sound from silent drives, like putting a speaker on the LED path or something.

for PEntium 75-166 possibly, on a K6-3 450 only if you like the smell of burning silicone.

Hm. Couldn't find anything with the proper fixation. None of the big enough passive heatsink I could find had the latch to attach to the socket 7.

Found a picture on the net, wich looks exactly like the one that I got with my P-166 a long time ago.

jarreboum wrote:

Hm. Couldn't find anything with the proper fixation. None of the big enough passive heatsink I could find had the latch to attach to the socket 7.

not likely to find new ones, or even used ones that way, Socket 7, Socket 370 and Socket A all share a common mounting mechanism and there for awhile from about 1998 they made 7/370 coolers, from 2000-2002 7/370/462.

A socket 370/462 cooler will work on 7, just be aware its going to be a very tight fit, and one of the socket 7 coolers for Athlon XP will work without a fan on your application as long as you have room around the socket.

The P3 500 Katmai and 600EB cards I've got are both passively cooled, although the heatsink is gigantic on both. I'd say you'll be fine.

might be a good idea to get Pentium 133+ and underclock it to 75Mhz as 75, 90 and 100 MHz parts were fabricated using 0.5 mkm tech and 133 (or 120) and later parts used 0.35 mkm. 0.35 should consume less power as CMOS gates would have less capacitance.

I have some of those speed-controlled case fans that have a 3 speed switch. When set to the lowest speed, I can't hear the fan with the case closed, so if you set this to blow across the HS fins, that might do the trick.

My Compaq Presario 4766 came from the factory with a Pentium 166MMX which was passive cooled with a larger than ususal (for the time) heatsink. I overclocked it to 200mhz, and it was still rock stable.

I had a fanless Pentium 3-933 and it worked perfectly.

This thread should be renamed to "The passive heatsink CPU tales" 🤣

I once had a fanless Athlon XP, but sadly it lasted a whole 2 minutes before it died 🤣

jarreboum wrote:

Would something like this be enough for anything socket 7 then? […]
Show full quote

Would something like this be enough for anything socket 7 then?

http://www.ebay.com/itm/391229723676

James-F wrote:

If noise is the main reason for running fanless, HDD is one of biggest noise makers.
Go Solidstate or SD card IDE controller for totally silent system (and much faster).

I'm using a Compact Flash with an IDE adapter. The thing is completely silent and extremely fast, but I do miss the HDD noise: it was a reminder that the computer was indeed working and just didn't hang in the middle of a process. The HDD light doesn't do the job imo, as you have to look at it. I do wonder if there are mods to bring back some sound from silent drives, like putting a speaker on the LED path or something.

For 75 to 100mhz but when it comes to passive cooling bigger is always better as there is more surface area to dissipate the heat. If all else fails and you can't find a period accurate cooler that is large enough let alone fit you could consider buying a socket A or 370 cooler then take the fan off. Copper is always nice especially when the price is low enough.

EDIT: Quick buy this one and mod a clip to mount it!!! http://www.ebay.com/itm/Zalman-copper-heat-si … 2937022?_trksid

To add to what's already been mentioned here, the older and more slow s5 and s7 Pentiums were very commonly fitted with the large passive heatsinks like the one pictured here

Thandor wrote:

A Pentium 75 is able to run without heatsink without crashing (although the intense heat doesn't do it good). With a big heatsink it wouldn't be a problem to run Pentiums without active cooling. In Compaq systems (fitted with Pentium 75 ~ 100) I found heatsinks like these (not actual picture, but similar). I'm sure these will run fine on a Pentium 133 as well.

These large passive Pentium 1 heatsinks were all over the place (often using heatsink latching clamps without holes so it was more difficult to remove them with a screwdriver) and many were that particular green color.

But these heatsinks typically have a much thinner base compared to s370 heatsinks, even though those older Pentium 1 heatsinks were fysically longer and wider. I tried to draw a quick & dirty pic to explain what I mean with this base.

This thinner base will affect cooling I presume.

The heat sink has to be the right thickness to maximize heat conductance to the fins while maintaining small enough heat resistance from the base.