Thanks for the ideas.
MP3boombox,
That's what I first thought and I have already desoldered-resoldered the whole switch once. Although the pads of R130 may still be the culprit, I have to look into it.
Badflash,
> You don't say what your FSB is set to
110 MHz.
> but the IO will not boot above 300Mhz.
Gee, I didn't know it. Any specific reason?
But then anyone running a non-DOS OS has to write his own k6clk for running above 300MHz?
Apart from this I was unable to change the multiplier with the Winchip as well (of course, FSB was 67MHz), so I would think it is of the contacts.
Geo