At a disadvantage (2011) – Which was faster, an IBM PC or a Commodore 64?

Also the Commodore did not boot, it just started right up.

The PC started much slower, especially since they had to boot to a disk of some kind, definitely a slow 5.25 inch floppy on the first PC which is when Commodore was already well-established.

PC's also had no audio, color, or graphics, only internal beeper tones and monochrome text.

In the Game Boy, the CPU is (broadly speaking) an 8080 derivative[0] running at ~4MHz. But all of the instructions take multiples of 4 cycles to execute, so when discussing clock cycles on the Game Boy, (homebrew) developers generally talk in units of four. That is, the CPU is considered (to the programmer) to be running at 1MHz.

Note that that's an 8080 -- not an 8088, but I mention this because of the point in the article:

> effectively turning the IBM PC from a 4.77MHz computer into a 1.1925MHz computer.

[0] The SM83 CPU core, made by Sharp, is often viewed as something in between an 8080 and a Z80.

This feels like programming an 8088 like it's a 6502. The 8088 has a lot more general purpose registers than the 6502, so variables would tend to be kept in registers while they were being worked on. The encoding for

  ROR reg, 1

is only 2 bytes - so 4 cycles for instruction fetch, then another 2 cycles to execute.