The quickest way to surely bring down a Windows 9x
- Open a DOS console
- Start debug
f 0000:0000 ffff ff
What happens is that we overwrite the "zero page"
(which contains the interrupt table; including the
IRQ vectors). Anything interrupt related (including the
IRQ0 timer executed (normally) 18.2Hz) will make the
processor jump to ffff:ffff, which doesn't contain any
sensible code. Windows 9x is unable to recover from this.