Does the Pentium MMX 233 need active cooling?

[AnitaPeterson]

Hi there,

This evening, as I was putting together a machine from old parts, I came across a Socket 7 P233 MMX, which I fitted onto an ASUS VX97 motherboard...

Next, I discovered a very large and deep (or tall) passive heatsink for Socket 7, so I put that on top of the CPU... the machine was nice and very quite - compared to modern ones... After running for about 30 minutes, the heatsink was quite warm, but not too hot to touch.

So I'm wondering... will the CPU eventually require a fan on the heatsink, or will it be OK like this... and just how hot is TOO hot for a CPU in that class? I mean, I've seen P166 with smaller passive heatsinks glued directly on them, is the 233 MMX that much hotter?

 

[slpaulson]

Try stressing it with prime95. If it doesn't lock up it's fine.

 

[sharkeeper]

no it should be fine

 

[AnitaPeterson]

I'm thinking about running a few games of Strife and Duke Nukem 3D on the machine... I guess a lock-up is the worst that can happen, right?

 

[imported_Kiwi]

Fans had been added to Pentiums from early in their production. ptobably from about 166 MHz, but the builders then would balance case size and air flow with heat sink choices. I have seen branded P-II systems with passive heat sinks, but they were truly huge things when found on the 300- 350 cpu's. From 400 MHz upward, P-II, P-III, K6, almost all went to using fans on the heat sinks.

My own P-I MMX 233 had a hsf combo on it when it was built.

 

[Arcanedeath]

No they don't if you use a large enough heatsink and have decent case airflow

 

[AnitaPeterson]

It's one of the computers I'm building for my Romanian charity project... I won't have it around for too long, that's why I'm trying to figure out if it's OK to leave it like that. I guess I shouldn't be worried.

 

[dexvx]

Depends on case airflow, but most chips at 233MMX had a small fan on it.

Today's heatsink and thermal-pastes are much better than when the 233MMX first came out, so if the heatsink is newer and you use new thermal-paste along with good case cooling, you should be fine with passive cooling.

 

[fire400]

if you want it to run for an extended period of time, it wouldn't hurt to put a cooling device on it, you never know when something will need it, maybe a part in the rig goes out of control and starts to heat up? for this reason, risking the cpu to not have backup cooling is suicidal.

I remember the Radeon 7000 32meg PCI card being built without a fan. Sure it wasn't as fast as a Geforce 2 Ti 32meg AGP card, but considering that it was using a possible engine that needed some type of cooling, it was necessary because lower speeds didn't actually mean it would be cooler than it's older sisters. I guess the latter Radeons in the 9K series didn't need it because of more effective ways they were engineered.

but I mean, you could find a 233MX CPU for 10 bucks at a garage sale.

 

[StrangerGuy]

Nope, if the heatsink is large enough. They are some of the coolest chips I have used.

 

[Googer]

Originally posted by: sharkeeper
no it should be fine

Yes it does need cooling. I Had a 166 and 200 Classic Pentium and burned my finger when i removed the heatsink. I can remember some 486's (DX4's) having small (southbridge sized) heatsinks. Even some older 100-133 MHz had heatsinks.

Do put one on a 200 MHz Pentium they are not optional but requred for this processor. Do not do it and you may have a melted socket the next day.

EDIT: Most socket 370/Socket A heatsinks will work, but it's over kill. I have used a copper swiftech mcx370 on a Pentium 200

http://www.directron.com/mcx370c.html

 

[Googer]

Originally posted by: Arcanedeath
No they don't if you use a large enough heatsink and have decent case airflow

Decent airflow was not needed back in those days, usualy the PSU was suffciant enough to wisk the heat away.

 

[AnitaPeterson]

Hmm, I guess it's a good idea to post some pics... at least for illustrative purposes

Here's the heatsink seen from the outside
and here's a lateral view.

I'll run some gaming and such for a couple of hours, and then place a thermometer on the fins... what's the temperature value I should worry about?

Speaking of fans and heatsinks, since you guys mentioned the Radeon/GF2 rivalry, I just replaced a dead "original" HSF combo on one of my ASUS v7700 Deluxe (GF2 GTS) cards, with a copper heatsink just a tad smaller than the one in the picture... the machine runs 24/7 without any issues.

 

[Googer]

Originally posted by: AnitaPeterson
Hmm, I guess it's a good idea to post some pics... at least for illustrative purposes

Here's the heatsink seen from the outside
and here's a lateral view.

I'll run some gaming and such for a couple of hours, and then place a thermometer on the fins... what's the temperature value I should worry about?

Speaking of fans and heatsinks, since you guys mentioned the Radeon/GF2 rivalry, I just replaced a dead "original" HSF combo on one of my ASUS v7700 Deluxe (GF2 GTS) cards, with a copper heatsink just a tad smaller than the one in the picture... the machine runs 24/7 without any issues.

As a generic rule anything over 122°F or 50° C is cause for some concern

Get a fan and some thermal paste on that sucker. That heatsink is on backwards DUDE!

 

[AnitaPeterson]

Hmmm.. it's not backwards... 1) see the first picture, if you look at the left side, it's V-shaped, not straight, that's where the clip goes... besides which 2) putting it with the V facing right is impossible, because of the HD cage. And yes, there's a lot of thermal paste on top of the CPU.

 

[Googer]

Originally posted by: AnitaPeterson
Hmmm.. it's not backwards... 1) see the first picture, if you look at the left side, it's V-shaped, not straight, that's where the clip goes... besides which 2) putting it with the V facing right is impossible, because of the HD cage. And yes, there's a lot of thermal paste on top of the CPU.

After a second look I think you are right. It can be tough to make a judgement sometimes when all you have is a 2D image. I was looking at the second picture and it looked backwards, but I suspect that is due more to the camera angle and my visual cortex.

 

[aidanjm]

I had a 233 pentium. It came with a passive heatsink, and never seemed to have problems with overheating.

 

[CrispyFried]

Ive seen 233 mmx's both ways.. but with the passive sink there was a shroud from the hs to the PSU fan. so unless the passive sink has decent airflow Id add a fan. I will say though that my buds 233 with the passive sink was *totally* clogged with dust and dog hair and ran that way for like a year and never had a problem.

BTW I OCed my 233 mmx to 300 no prob (4x75, active cooling) for about a year and it still ran fine when I retired it.

 

[PremiumG]

the fan that you will use to cool the Pentium 233mhz is worth more than the CPU.. save the fan for a motherboard or videocard or something