Switch the drives. Put the SSD where the HDD was. If that doesn't work, remove the HDD, and install Windows on the SSD in UEFI mode (worth it, much faster boot time - 2-4 seconds tops). After you finished installing windows in UEFI mode on the SSD, plug in the HDD, enter BIOS, go to the last pannel, and under boot override select UEFI:SAMSUNG whatever model it is. It will boot off the SSD. Once you're in windows, delete all partitions on the HDD, create new ones (empty) and restart. Now it won't boot off the HDD because there's no OS on it to boot from.
I have a hunch ASUS wants us to keep the machines as they are. That's why they put the stock 8gb of ram under the palmrest, and make it difficult to bood from a SATA SSD. I've had several issues until I installed Win 8 in UEFI mode.