Some sentient computers or droids can, after being left alone for millennia alone, develop severe impairments in their AI. These are analogues to mental illness or madness in a human, and is generally referred to as "Computer Senility". Holly, the computer which controlled Red Dwarf, originally had an I.Q. of 6000, although this was greatly diminished after the accident and spending three million years alone, resulting in Holly becoming an idiot and borderline crazy. Some more severe cases of computer senility have resulted in murderous droids, such as Hudzen-10 or Asclepius.
The multitude of A.I.s aboard Red Dwarf eventually united and rebelled against the crew, although the crew were able to placate the A.I.s by voting a member of the crew the position of "Machine President" to represent their rights. ("Mechocracy")