3 ms·

If you expand that to Z80 compatible chips, the fastest was (is, possibly, as I think it's still being made) the Zilog eZ280 at 50 MHz -- which, given that it r

If you expand that to Z80 compatible chips, the fastest was (is, possibly, as I think it's still being made) the Zilog eZ280 at 50 MHz -- which, given that it runs at about three times as fast as the Z80 at the same clock frequency, is like having a 150 MHz Z80. https://en.wikipedia.org/wiki/Zilog_eZ80 https://en.wikipedia.org/wiki/Zilog_eZ80 My TRS-80 Model 4 back in the day (circa 1988, I think) had been upgraded with a HD64180 CPU, which apparently could run at least at 10 MHz -- although I'm pretty sure the third-party expansion board I was using ran it at 6.144 MHz.

Gracana 7y ago
You may be aware, but to add to your comment... Good ol' Z80s are still in active production as well, and you can buy a 20MHz chip in a DIP, LQFP, or PLCC package. Anyone who is interested should check out the RC2014 and retrocomp google groups. Lots of discussion there, and there are a few people selling Z80 and Z180 computer kits. https://groups.google.com/forum/#!forum/rc2014-z80 https://groups.google.com/forum/#!forum/rc2014-z80 https://groups.google.com/forum/#!forum/retro-comp https://groups.google.com/forum/#!forum/retro-comp