Comment 29 for bug 210780

This is apparently still a problem with the intrepid generic kernel only i get a different error in dmesg than the original poster:

[ 28.428465] mtrr: type mismatch for e0000000,10000000 old: write-back new: write-combining

i went from 1gb to 4gb and my mtrr looks basically the same as the OP and the others with no 256gb section.