BTW, it's been a while and I don't recall if there's a standard tool for dumping MTRRs. If not, the attached tool should still work. You an build/run it via:
# mv /path/to/show-mtrr.c.txt show-mtrr.c
# gcc -o show-mtrr show-mtrr.c
# ./show-mtrr
The program needs to be run as
root.