I once tested all of my MMX chips, but I don't remember where I wrote down the results and if I ever posted my results here. I only tested for their maximum multiplier btw, iirc.
And in the end it appeared that some had some of their multipliers disabled and some were multiplier free.

I do remember a webpage that explained how after a specific date chances increased the lower speed chips had disabled 3.5x multi etc, but can't really remember as it is so long ago.

I still have the p233 mmx installed, but now I'm curious about the x1.5 multi and may swap the p200 back in test it out. If I do I'll report back..

tincup wrote:

I still have the p233 mmx installed, but now I'm curious about the x1.5 multi and may swap the p200 back in test it out. If I do I'll report back..

AFAIK the MMX do not have a 1.5 multiplier, 2x is the lowest.

The standard Pentium interprets 3.5 as 1.5x or something like that.

Hmmm.. my notes in the margins of my AN430TX manual show I under-clocked the P200 mmx to 90mhz using 60mhz @ x1.5 jumper settings. Notes also indicate I could not achieve the same result using a P233 mmx - it read the x1.5 jumper setting as x3.5.

I'll definitely give it a try.

I stand corrected. None of the MMX cpus saw the x1.5 multi, but the non-MMX did. Bad notes haha!

No problem, thanks for checking.

gerwin wrote:

Pentium MMX 200 SL27J 5.4.3 - 2.5x, 3.0x

just for the record with that one I can get it working on: 120Mhz, 150MHx, 180MHz and of course 200MHz.

Pictures of the CPU and screenshots from SpeedSys are attached.

On 120Mhz with cache disabled it goes does to 386DX 40Mhz.

So, those are the modes - 4 possible speeds and with cache disabled depending on the speed it is between 386DX 40Mhz and 486DX2 50Mhz (it cannot reach that speed and it's less than that and so maybe it's more correct to say between 386DX and 486DX 40Mhz).