Unable to enable XMP in Bios

[Mr.G]

I have a HP Envy h8-1520t desktop with a Pegatron Motherboard IPMMB-FM Formosa socket Z75 LGA1155 running an i7 3770 3.4Ghz. I just purchased G.Skill RipJaws PC3-12800 DDR3-1600 CL9 16G kit (8gx2) intel XMP ready. I installed them and the are running at 1333mhz instead of 1600mHz, Ive searched the Bois for a place to configure memory or somewhere to enable XMP and have had no success. Am I missing something or just out of luck, The only information I can retreive on the Motherboard is on the HP website and they give no info about overclocking or changing memory timings. Any input would be greatly appreciated.

[Tradesman]

There should be a clear CMOS jumper on the mobo (should be in the manual), could try that, also check to see if there is a newer BIOS...This is often a problem with off the shelf systems as they often have a locked BIOS that doesn't allow many changes...Would also contact them direct as their specs on the system readily state it will run 1600 sticks.