alt Hacker NewsThe floppy disk usually made this straight up honking noise . I had a V20, but at 10Mhz. Never had a problem, except for formatting floppies. The V20 has a few tricks up it's sleeve, with a few less clock cycles on some instructions, and a Z80 mode to run cpm.
But,the real trick was to put real IBM roms in a clone board and run Xenix. When the clone roms are back in it still booted. Helped a lot to have a 2:1 Rll controller. Xenix was just pollute and delute - system V with some BSD thrown in and a slightly altered portable C complier that was later admitted to be wrong endian.
Did this Board have a FPU socket? Made turbo pascal run much faster. ( The 8087 version we got from the physics lab...) Especially the Hilbert matrix. And FFTs.
Z80 mode to run cpm
8080 mode, not Z80. Did run CP/M, and I used 22nice for probably longer than needed. Unfortunately over time lots of cool software assumed a Z80, sooo...
Xenix was just pollute and delute - system V with some BSD thrown in
Which Xenix? It was originally V7 based, and 'upgraded' to System III around version 3. I forget what it looked like between version 3 and version 5.x, where it became System V based (+ stuff).