The speed that u see in the BIOS should be mutiplied by two because ur RAM works in dual channel (800x2=1600) go to windows download CPU-Z and check the RAM frequency in the RAM tab if u see 800MHz ur RAM is working at rated speed.
If u want more help, please post all the specs of ur rig and maybe a pic of the problem can help too.
I have not more ideas, in the pics that I see of ur mobo's BIOS doesn't options to set the RAM manually and change the timings. You can try with the ASRock support, they should help u to solve the problem or u also can RMA the mobo and get another one from ASUS, Gigabyte or MSI.
Found my system quite slow, therefore I was investigating the problem, what lead to this page.
I have the same configuration same problem, but did see my BIOS version (Mainboard tab) shows P1.00
Meanwhile they brought out Version 2.50. So I will upgrade my BIOS to see the memory modules get the right settings, let you know what it does.
Yes, with the new BIOS-version I do get the right Frequency of 800Mhz.