Unforunately, I don't have a spare PSU, as my previous PSU (OCZ 430w) is being used in my brother's computer when his PSU died. The OCZ 430w definitely cannot provide enough power to my system now.
As for cabling its definitely a possibility as I am using only the generic red sata cables include with my motherboard. I have the newest drivers from Asus' site since Marvell (QLogic technology) is completely worthless for non-LAN/NIC drivers.
My guess is this problem is either a random RAID controller failure, which is due to the integrated nature of the controller and not really fixable with the hardware. Only buying a 130+ USD PCIe RAID controller will help.
Since it has not done any damage, and my system doesn't require 100% relability. I am not going to stress over it.
BTW: The last time I called Asus for anything, they were completely worthless and acted like -- "How dare you call us..." :P