unexpectedly yesterday (from my usual IBM PC330DX4) I extract the intel 486DX4 and put the Cyrix 5x86 without changing any jumper. I had already tried the various 486 class cpus that I had but without success by changing the various jumpers on the mainboard. I had also found an IBM document that gave me little hope of its working and mentioned incompatible chipsets and interposers. This time, however, without changing anything SBAM! everything works. The boot takes a long time (as per IBM tradition) but the computer loads the operating system and I can do the philcomputerlab tests of Domm and Quake. So I put the POD on and it works too! Fantastic! Later I realized that I left the DX4 3.3v voltage regulator plugged in. Am I running the POD at 3.3v? I don't think it will ruin, but is it stable and maybe it warms less?