Plastic Pentium MMX has integrated heatspreader.

The ceramic version gets hotter, that's why it is enclosed in ceramic. The plastic version was optimized in production and produces less heat. Technically, they are identical in specs.

I think the first intel x86 CPU to use the plastic version was the P200 sans MMX. It got too hot for the ceramic packaging. When Intel started making the MMX chips, they used split rail voltages with reduced core voltage, which in turn reduced heat dissipation allowing the P166MMX and P200MMX to go back to the older ceramic package...perhaps until they used up whatever supply they had lying around.

There's both ceramic and PPGA version of quite a few P5 models: classic 166/200, MMX 166/200 (desktop models). The insides are the same, I presume. The metal heat spreader should be better at transferring the core's heat to the cooler. Btw I have both kinds of 166-sans-MMX and both are stable at 200MHz.

AFAIK, the MMX-233 doesn't have a ceramic version, though, while the old classics below 166MHz are always ceramic.

I asked this because I have a card with the 233mmx with the heatsink glued on and produce a very annoying noise. Unfortunately I can't install another CPU in plastic because the socket is not ZIFF and therefore it does not have hooks to block the heat sinks. I have to choose the heatsinks that hook directly to the CPU, and from what I know exist only for ceramic CPUs. That's why I wanted to use the Pentium MMX ceramic instead of the plastic version. Even if the ceramic version I own is only 200mhz I don't think it's too slower than the 233mhz plastic version. I forgot to tell that my board is a ss7 and bus can run at 100mhz, i can run my cpu at 100x2=200mhz. I think is really fast that the regular 233mmx (that can run at 100x2.5)...

AlessandroB wrote:

...the regular 233mmx (that can run at 100x2.5)...

With some luck even the 200 can do the same. (Though the ceramic ones are usually from earlier batches so you have worse chances than with newer plastic ones).

alvaro84 wrote:

There's both ceramic and PPGA version of quite a few P5 models: classic 166/200, MMX 166/200 (desktop models). The insides are the same, I presume. The metal heat spreader should be better at transferring the core's heat to the cooler. Btw I have both kinds of 166-sans-MMX and both are stable at 200MHz.

AFAIK, the MMX-233 doesn't have a ceramic version, though, while the old classics below 166MHz are always ceramic.

According to my own homemade Excel sheet, there is no ceramic 200 Classic. Was I wrong when making it?

Was I wrong when making it?

Most likely not. Ceramic P200 were relabeled P166: https://www.cpu-galaxy.at/Article/fakes.htm

The Serpent Rider wrote:

Was I wrong when making it?

Most likely not. Ceramic P200 were relabeled P166: https://www.cpu-galaxy.at/Article/fakes.htm

Very interesting 😀

H3nrik V! wrote:

alvaro84 wrote:

There's both ceramic and PPGA version of quite a few P5 models: classic 166/200, MMX 166/200 (desktop models). The insides are the same, I presume. The metal heat spreader should be better at transferring the core's heat to the cooler. Btw I have both kinds of 166-sans-MMX and both are stable at 200MHz.

AFAIK, the MMX-233 doesn't have a ceramic version, though, while the old classics below 166MHz are always ceramic.

According to my own homemade Excel sheet, there is no ceramic 200 Classic. Was I wrong when making it?

As i remember 200 classic is ceramic, then, when the 166mmx plastic come out, intel start to mix plastic and ceramic ,but 200 ceramic was made for sure.

Try to find one that isn't fake. I gave it my best shot but came up empty handed.

The Serpent Rider wrote:

Was I wrong when making it?

Most likely not. Ceramic P200 were relabeled P166: https://www.cpu-galaxy.at/Article/fakes.htm

I thought there was a very normal ceramic 80502200. So it was a fake...?

WANT 🤣

Hello,

I’m new here but loving hardware since decades. I’m taking the liberty of digging up this topic as I came accross what’s seems to be a Pentium 233 MMX in a CPGA package (ceramic, then, not plastic PPGA) but its sSpec is SL27S which relates to a classical PPGA P233 MMX. Also, I don’t find any mention of any CPGA P233 MMX anywhere else.
I haven’t tried to scratch it to see if it could be a relabelled P200 MMX (or even a P166 MMX) but the engraved numbers and printed labels seem pretty legit so far. What do you think? I also enclose the bottom of the chip, which printed stuff looks rather faded out.

Thanks for your advice on this!

Oh that is interesting

I also have a curiosity, a 200mhz sl27s ppga

Sphere478 wrote on 2023-07-09, 08:34:

Oh that is interesting

I also have a curiosity, a 200mhz sl27s ppga

So same sSpec ID but different speed. I tend to think that the SL27S speed is 233 MHz, as per the various websites referencing it. Is yours labelled as 200 MHz or is running at 200 MHz (and could run faster)?

Los Pebos wrote on 2023-07-09, 10:26:

Sphere478 wrote on 2023-07-09, 08:34:

Oh that is interesting

I also have a curiosity, a 200mhz sl27s ppga

So same sSpec ID but different speed. I tend to think that the SL27S speed is 233 MHz, as per the various websites referencing it. Is yours labelled as 200 MHz or is running at 200 MHz (and could run faster)?

labeled, I should check to see if it has the 3.5 X option enabled I suspected it probably does, though maybe not.

Los Pebos wrote on 2023-07-09, 08:12:

but the engraved numbers and printed labels seem pretty legit so far. What do you think?

For one the front-side dark engraved copyright symbol is odd. The ends of the letter "c" in the circle do not meet close enough.
Fortunately, Asian counterfeiters tend to lack feeling for latin typography details.

The marks on a ceramic are laser, if you look at it under a micro scope it becomes obvious very fast if it is melted ceramic or paint

Fake. The way the laser burnt looks wrong and the copyright symbol is too comical.

Give it a scrape with sharp knife, the top layer should come off. I have a remarked Pentium 150 as 166 like this.

Cheers,