Re: XPS 730x H2C loses power / resets / reboots "randomly"...
Not meaning to barge into this conversation, as I have just a plain old 730 H2C, with only a QX9650 OC to 3.67, but IMHO Richsi seems on the correct tract. My system has the same random shut downs, ran the same diagnostic, got the 2000-0123 red herring (which tech support in FL said was not the real issue after taking each memory module out and puting into DIM #1 and rerunning the diagnositc for each module).
They are replacing the cooling unit, CPU and fans this Sat. morning. The main difference is that my system did not start the random shut downs and BSOD until months after I bought the system, but it has progressed over these past few weeks.
I will be watching the 730X board more closely now.