[Just speculation] I think they've dropped MSDM table as there is a loophole: one can get the MSDM key & use it as a retail key to activate another device by phone activation. As far as I remember, Please-8 himself discovered & posted it in MDL. Now for the OEM: DM activated devices, HWID + unique OEM: DM key are saved in MS activation servers.
OK - possible. But how do that the OEMs practically. Do they inject every hdd image with an individual OEM key ? (In Windows 8 the OEMs inject every BIOS with an individual OEM key)
If we find another win10 system, it would be easier to tell. I can only assume they OEM setup is done at the OEM. Win8/8.1 OEM would contact MS for each system (automated), authenticate -> request -> get -> tattoo each system. Now they may have gone back to Win7ish type and have a single image as master image and just build their doodoo machines. Looks like combo, OEM do their thing and still do the auth->req->get->tattoo for the system.
What does the following mean: I have a DVD with Windows 10 x64 Home and Pro (downloaded from Microsoft). When I use this DVD for an installation in a virtual machine the setup ask me for a key (to make a decision between "Home" and "Pro") When I choose "skip key entry" then the setup offers a menu with both versions. When I go back and enter a key (e.g.: Win 10 RTM Core OEMM) then the menu with the both versions doesn't appear (because I have made my decision by entering a "Core / Home" key) When I boot from the same DVD on the new notebook I don’t see any key question or menu. Setup installs automatically the Home version. Same procedure like Windows 8. So I think a unique OEM key is still there in the BIOS - but not in the MSDM table.
If you have OEM key just download windows 8.1 iso with rufus then make UEFI usb boot (link......../windows-8/create-reset-refresh-media -cant post links). Do a clean install 8.1 then reserve windows 10 and do just upgrade. You dont need to enter any key it will read from bios.
If know what keys have store here ??? HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\DefaultProductKey and HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\DefaultProductKey2
Some keys are there (this is hidden key): HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\DigitalProductId