I've found this on the FAQ's page for your motherboard.
Q. Why can't I enable some RAID function?
A. Due to the limitation of PC structure, the capacity of shadow memory is fixed. If the shadow memory is not enough, some of the RAID controllers will be inactive.
What is NV-RAM? - Nonvolatile Read Write Memory, also called Flash memory. It is also know as shadow RAM.
I'm wondering if there's a setting or restriction there causing you problems?
The USB stick isn't in the port at bootup?
Is "plug n play O/S" disabled in bios or enabled?
Have you tried with 1 stick of RAM to start the process?
Not sure why that error is logged for your motherboard as a faq. Maybe an email to them regarding this?
The only thing necessary for the triumph of evil is for good men to do nothing - Edmund Burke