Ah, I see. Good advice!

Try to find IBM branded Cyrix 5x86s, they reliably work at 120MHz (40x3) and with registers enabled easily match Am5x86-133 But that will leave me with 75MHz with my 25MHz FSB(25x3)? What I need is certainly 25x4, or rather 33x4 underclocked to 25x4?

I am aware that all the alternatives listed below would require a voltage regulator adapter, further hardware hacking or a processor with integrated voltage regulation to get the necessary 3.45V or 3.3V instead of the original 5V to the processor. ... My question is: can I expect 4x33 processors to …

appiah4 wrote on 2022-08-04, 12:59: Yeah they will work fine at 100MHz. Thank you for a quick reply! Now to ebay!

I have an IBM PS1 2133 (surface mounted 486SX 25 MHz) I have been upgrading lately, and I want to get more out of the system by upgrading the CPU. Currently I am running a 486DX2 66MHz underclocked at 50 MHz in the upgrade socket (I did the necessary hardware hack to get non-overdrive processors …