I just set up a Debian system with one of theses CPUs and I'm not getting any such error. One thing that strikes me as odd is that most of the k6-2 chips use a 2.2V core voltage and most of the HX based motherboards can't go that low so I'd double check that your motherboard and cpu really are compatable.
Does this happen even when the system is completely cold? How about if you underclock it a bit (say 60X4.5)? -- Ray [EMAIL PROTECTED]