It would depend on the board, and without knowing what it's doing generally it would be nothing. But it's always possible it could do bad things.

But it sounds like you might be modifying the CPU multiplier, this is read at boot and you need to do the power cycle to re-read it.

What CPU are you running? Since you have a Super Socket 7 you might have access to changing CPU multipliers on the fly via software with a K6-2/3.

Yes, just the CPU multiplier. I forgot to mention, sorry.

It's a K6-III 450. As far as I know, you can only change the multiplier on the K6-2+ or K6-III+ via software.

But it sounds like you might be modifying the CPU multiplier, this is read at boot and you need to do the power cycle to re-read it.

On every board?

I am using switches to change FSB and multi on an SS7. That will change 133 MHZ to 266 MHz or even 500 MHz.
I have done it by accident several times with the machine running. IIRC, nothing happens. At least it didn't break anything. But it won't work without reboot.

Thx!
Changing the FSB from the outside would be possible on my board, but it would be very time-consuming. Three pins, two of which always have to be connected. Setting 1-2 or 2-3.
Changing the FSB to 66MHz and a clock speed of 166 MHz would be a little better, but not much.

I have tested it. Nothing happens. The clock only changes when the PC is restarted. The PC doesn't have to be completely off. Control + Alt + Delete in DOS or Restart in Windows is enough. Thanks for your information.