Undead Chip-head Defined.

Undead Chip-head - Technology adapted from observing and analyzing Vril body-snatching biology recreated technologically, allowing for copying of human consciousness onto a whittled down super advanced computer chip.
Chip is then re-inserted either into clones of the original person or a new body altogether to achieve human/human body-snatching through technology as opposed to Vril body-snatching through biology, a quasi-immortality technology used by the super wealthy as a way of cheating death.

References in movies - Self/less, The Matrix Revolutions (Smith), Mortal Kombat Annihilation (Raiden), Avatar, Chappie, X-men Apocalypse.

References in TV - Doctor Who, Battlestar Galactica, Intelligence, Black Mirror (Cookies)

References in Games - S.O.M.A

References in music - Grendel - Timewave Zero

Notes - An Undead Chiphead is not a human being, rather it is a flash copy of a human being's consciousness with that data being stored on a chip that while very advanced still no where near matches the complexity of the brain, therefore what you are seeing is more like a holographic representation of a person rendered by a computer than an actual person.
Now these consciousnesses may not be human but they still respond the same but the original person is dead, they cannot transfer your original mind to a chip but they Can copy one to it.
Undead chip-heads are not as creative as the original person, nor are they as intelligent or insightful, people are more than just memories and even though Undead chip-heads are very good simulations of people they are different to people. They are Simulations. Simulations can be tampered with this is probably why like in pet Sematary the people who come back, come back kinda wrong, its most likely programmed in to maintain control. What has happened with chip-heads is that we've essentially just taken a computer A.i. and given it memories and structure which makes it think it is a human being, regardless of your definitions of life, its still a travesty of one.

There are many people who are in power or famous who are chip-heads of people long since dead and the issue we have is seeing these people not as people, they are more machines riding a human body than an actual human, they can be switched off at the press of a switch, imagine if the holographic characters from Star Trek's holodeck started to run amok which Has happened in at least a few episodes, that is what you are dealing with when you are dealing with Undead Chip-heads.
Not all Chip-heads used to be human, many used to be drones, Undead chip-heads of drones, or other creatures, its all the rage in terms of using it to achieve some level of immortality which these people desperately crave.. Eternal life, even in a crude Undead technological way.
The TV show Black Mirror has for years being showing this concept and the levels of evil you can do aware simulations of people, often they get tortured in extreme ways.

Its like torturing people in the game The Sims but they can tell you just how much they are suffering.

Could this be used for good? Yes Just like Holodecks on Star Trek so that future generations might learn what a person was like but for now its just used for evil and extreme torture by people who lack conscience.

Thats enough about that.