I found the cap as you described and have both power connectors properly attached however the post problem still exists. I end up with code A2 and the yellow light next to the PCIE lane one switch on. I have tried two different sets of memory, installed a known working GPU from another working system. I have tried two different optical drives attached to the black sata ports.
I still have a dark screen. I am waiting for a new DVI video cable to ensure the analog to DVI adaptor is not the problem for the dark screen. Additionally, I have tried two different bios versions.
What else can I try to isolate the problem which seems at this point to be the MB?
edit: I called ASUS support. They suggested powering down completely by removing the battery and clearing CMOS. Any other ideas?