My PC is water cooled. However the VAX 9000 wasn't. It was initially designed to be water cooled but during development they improved the air cooling enough th

My PC is water cooled. However the VAX 9000 wasn't. It was initially designed to be water cooled but during development they improved the air cooling enough that water cooling was never shipped. One VAX 9000 CPU did around 70k Dhrystones/sec, so 40 VAX MIPS (DMIPS as we call them now). A modern simple RISC 5-stage in-order CPU (e.g. Berkeley RISC-V Rocket) with decent branch prediction does 1.6 DMIPS/MHz, so will need 25 MHz to match the VAX 9000. However the December 2016 HiFive1 ran at 320 MHz, so would be around a dozen times faster than the VAX 9000 -- but without FPU or MMU. Today, a $5 Milk-V Duo running at 1 GHz (64 bit, and with MMU and FPU and vector unit) will be 40x faster than a VAX 9000. The VAX 9000 has a vector unit, capable of a peak 125 MFLOPS. The Duo's C906 VFMACC.VV instruction has 4 cycles latency, for two 64-bit multiply-adds or four 32-bit multiply-adds, so at 1 GHz that's 1 GFLOP double precision or 2 GFLOP single precision, 8x a VAX 9000. Don't even ask what a modern i9 or Ryzen can do!