A while ago I've been told that some generic-brand PC, (yet packed on an IBM5150 case) had the ability to become a 80386 upon pressing Ctrl-Alt-Del (warm reboot) ?

I guess there might have been (for sure) another processor in them but I've been unable to find details online about these mid-80's beasts.


Some information about a similar concept in a September '86 magazine

Another thing from April '87

Some Linux stuff about Ctrl+Alt+KP+

But as far as I remember it was Ctrl+Alt+Del and there was no turbo button on the machine.

A guess is that it's what we used to call IBM PC and compatibles back in the time (a clone) :)

  • 2
    It could have been a real / protected mode confusion.
    – wizzwizz4
    Aug 23 '16 at 14:37
  • Possibly, I had access to this PC when I was ~6 years ... couldn't really figure it out at the time. One of the things I do remember though, was that some hippie came up home, de-soldered a few ceramic capacitors because supposedly it would run better without them :)
    – aybe
    Aug 23 '16 at 19:28
  • I actually have a Breakthru 286-12 board (the board reviewed in your second link), but speed is toggled using a switch on the expansion card (which ends up on the back of the PC), not using software. Aug 23 '16 at 21:05
  • Ctrl-Alt-Keypad + and - was used in Linux to switch video modes by the driver, and had no relation to any hardware. Apparently on a few motherboards this key combination also enabled/disabled turbo mode (faster clock), which was normally done by some extra front panel button, but again this doesn't mean a processor "switch" to 80386, nor a reboot.
    – dirkt
    Aug 24 '16 at 14:59
  • @StephenKitt it's interesting how with 'Breakthru 286-12' keywords I do find much more literature online about this era :)
    – aybe
    Aug 24 '16 at 19:05

What you describe sounds like the PC Elevator:

The PC Elevator 386 is a coprocessor-type accelerator board. The system's native CPU remains available for any programs that are sensitive to speed or timing. Software commands (Up for the faster 386 mode and Down for the slower speed) make speed selection simple. Initial startup via the Up command requires system rebooting.


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