The reasons an engine has difficulty starting up in cold weather are that 1) ignition spark plugs draw power from batteries which depend on chemical reactions that speed up at higher temperatures, and 2) lubricating oils that allow an engine to run smoothly get more viscous at lower temperatures. And the primary reason an engine would fail at high temperatures is that raw metals expand and contract more noticeably than other materials in an engine, such as alloys, and many engines are designed with a rather limited (but practical) thermal tolerance, beyond which moving parts would experience too much friction to sustain operation.
A car engine is to a CPU as apples are to oranges. There is no "ignition" temperature to reach in a CPU, nor are there supposed to be chemical reactions in an operating CPU, which is a solid-state device (no moving parts). Upper and lower temperature bounds for CPU operation mostly have to do with technical limits imposed by a particular manufacturing processes. I don't know that much about CPU manufacturing, but a much cited example is that recent AMD CPUs don't operate at liquid nitrogen (LN2) temperatures, whereas most o/c records for Intel CPUs continue to be set using LN2.