List your complete system specifications for me please. Also when your system is stucked at the 99 QCODE, please look beside the 24 pin power connector and indicate if any of the 4 QLEDs remain lit. 🙂
postcode "dd" doesn't stand for anything. I went through the same issue and contacted Asus about it. Their reply (after many emails) was that "dd" was a placeholder code for any future needs. It means absolutely nothing other than that there's an error that Asus has no answer for.