Interesting topic which computer/robotic villains are the most interesting/awesome due to their evil megalomaniacal computer programming acts on others & even in cartoons when inventions go
EVIL at times:evil:, here's alot of computer/robotic villains that I know:
Armstrong/Robotica/evil car robot(Ducktales) - Awesome evil robots who're the first inventions to go evil which Robotica the robot duck maid is cute/scary/psycho at the sametime

,eeeeekkkk!!!!!!
The Ultrabot 3000(Dexter's Laboratory) - Cool robot villain wanting to take over Dexter's Laboratory until when he's crushed by Dee Dee, hahahahaha, & he's voiced by Tom Kenny which was cool.
C.H.A.D.(Totally Spies!) - Computer geek's computer who's an evil megalomaniac with mass destruction in its mind, he was so awesome.
Comp-U-Comp(Dilbert) - Hilarious evil computer who's voiced by the awesome Jerry Seinfeld

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The Robot Mafia/Beelzebot/Robot Santa Claus/Roberto(Futurama) - They were hilarious robot villains along with their personalities & crazy antics, hehehe.
D.A.V.E.(The Batman) - Awesome evil robot villain with all the criminals' greatest minds who's Batman's best toughest opponent who knows his secret identity & that Dr.Strange created him which surprised me.
Silver Cyclone/The Tornado Champion/Tornado Tyrant(Batman:The Brave & the Bold) - They were awesome robot supervillains channeling Brainiac which they want to elimination to all humans, mechanical psychopaths much, hahahahahaha.
Lair-y(The League of Super Evil) - Hilarious evil security system built by Doktor Frogg who went psychopathic by taking over their lair, hehehehe.
big pirate robot(Dragonball) - He was Goku's best toughest opponent in the Red Ribbon Army/General Blue saga which looked like a skeletal version of the 3rd form Freeza, hahahahaha.
Woops, sorry about that zoombie, I'll learn to read topic questions carefully, hehehe, but that's a great question which by comparing them most computer/robotic villains can be more evil/diabolical by their technology actions than the regular living being villains that were just as evil, like for example in
The League Of Super Evil episode
LOSE vs. Lair when Lair-y proves to be more evil next to L.O.S.E. by kicking their butts, but L.O.S.E. were harmless villains though except for Doktor Frogg & Doomageddon who seem to be the most evilest of the group.