Dont think this is Win 8 specific but it affects my Win 8 Acer but not my Win 7 laptop,
In System Config there are three Start Up options, Normal, Diagnostic & Selective.
My Win 8 PC will run in Selective only, always reverts to that if I select either of the others.
All items are checked in Start Up & System. Have tried a few things to no avail like memory tests and sfc.
(On my Win 7 PC if I untick a Start Up item then it goes from Normal to Selective which seems reasonable? It returns to Normal when the item is rechecked.)