The Pentium III does sound like a good chip choice for a retro cyberpunk story. Like they said in “The Matrix”, 1999 was the peak of human civilization.
(586 became Pentium, so 686 would be the Pentium Pro/II microarchitecture.)
IIRC III was also 6th gen microarchitecture. Pentium IV was the 7th.
I remember 1999/2000-ish I had both a Pentium III/Intel motherboard and Athlon PC. The Pentium III system was rock solid, and performed fantasic. Even the CPU and motherboard looked amazing.
The Athlon was solid but less reliable, various reboots and glitches. I kind have always had a preference for Intel since then.
You can watch Serial Experiments Lain. It is an anime from 1998.
P6 chip. Triple the speed of the Pentium.
RISC architecture is gonna change everything.
The cartridge-style packaging of the Pentium II/III’s was also peak for the lineup.
My favorite PC I ever built was a dual-CPU Tyan motherboard that eventually held two screaming fast Coppermines. Needed a university copy of Windows 2000 to really make them sing—the Windows 95 series never supported SMP—and it was glorious.