To add some information to this thread which might be helpful I include below my list of updates for windows 8/8.1 which I think a user should avoid if they want to prevent GWX. There is a chance a few of these might be "false positives" (updates which I think might be GWX related but in reality are not) (if anyone recognises false psotives amongst them feel free to correct me) but having avoided them all myself I can say that not having them hasn't done me any harm and I have so far not had any GWX related things occuring on my systems. Also amongst this list are a number of telemetry related updates which some users would prefer not to have.
They are in no particular order, just the order in which they were written on my paper pad beside my desk...
KB3112336 (update to windows update client)
KB3021417 (on here because of a complete lack of description, nothing more known about this one)
KB3035583 (the main GWX related update)
KB3044374 (very similar to KB3035583)
KB3050265 and KB3050267(update to windows update client)
KB3065987 and KB3065988(update to windows update client)
KB2976978 (initial checking of system compatibility for upgrade, I think this update just runs a check and does nothing more)
KB3083325 (update to windows update client)
KB3083711 (update to windows update client)
KB3013816 (I think, but might have misread the description, that this forces use of an ms account instead of a local account and sets updates to full auto)
KB3046480 (reason for being on this list not remembered)
KB3058168 (reason for being on this list not remembered)
KB3075853 (update to windows update client)
The link to notebookreview.com seems to give the equivalents of these for windows 7
Edited by rp88, 16 December 2015 - 05:21 PM.
Back on this site, for a while anyway, been so busy the last year.
My systems:2 laptops, intel i3 processors, windows 8.1 installed on the hard-drive and linux mint 17.3 MATE installed to USB