Why are CISC processors used in server computers?

Going little bit deep on processor architecture right now.

CISC has lots of features:

  • more number of instructions
  • more addressing modes
  • more instruction formats which are variable in length
  • consumes more power
  • uses memory based operations
  • so less registers are required
  • but operations are multi-cycle leading to poorer pipelining performance
  • uses microprogrammed control unit
  • compilers need not be very complicated in CISC

None of these benefits suggest that CISC would be particularly suited for servers rather than real time systems. I am scratching my head since hours, googling since last 1 hour but cannot figure this out.

CISC is not inherently better for servers; it dominates the server market mainly due to historical x86 software compatibility and economic scale, not architectural suitability.

Real-time systems require deterministic, analyzable timing and low complexity, making simplified RISC-style designs far more appropriate.