JoeBar, the VDIMM problem is normal, all boards default to 1.80V but some RAM requires a bit more volts to boot at SPD. Just bad thinking on the RAM manufacturer's side, it's not ASUS's fault.
As for the PCIe X1, it's strange, but doesn't happen on all boards.

PS. Hyperthreading is for older P4 architecture CPUs, no need to worry about it.