you are correct in saying anything over 110mhz is pushing it, and you risk damaging components.
Going over 110 on the pci-e will not damage components. The only thing that might happen is the os/data on your sata drive/s might get corrupted and fail to boot. Most new boards sata controller are linked to the pci-e, so as you raise it above 100 the sata drive will start struggling to keep up.
This happened to me when I raised to 130, some people go way higher without any damage, with an IDE drive of course.