hi dsprad are you trying to run 1600ram? if so you'll need to do a few things.
After powering it on, press and hold the memok button near the dimm slots untill the led starts flashing. After this - you can let go, the system will set the memory to best stable configuration which most likely be at speeds of 1333. This may take a few minutes and will probably restart itself a few times while it configures itself.
If this works and you can enter the bios take note of the bios revision and update the bios using an usb stick. There will be an option in the bios to update, be sure to find the correct bios update from the asus website.
After and if you have successfully updated the bios, exit bios and turn off the computer, unplug the main power cable and remove the cmos battery. Then find the clear cmos button. It should be at the front io plate where you plug your cables into, should be labelled clear cmos/cmos or rather. When you find it, hold the button down for at least 20seconds. And do again with the cmos battery in for another 20seconds just to be sure its done the job. Shouldn’t need to take the cmos battery out, but with the mucking around im sure youre doing its worth it.
You should now be able to boot and load your proper rated configuration.
Hope some of this helps.