Post #4004711

2026-07-22 04:22 UTC

I just created EDA devices/symbols/footprints for Socket 7, as used by 90+ MHz Pentium, Pentium MMX, some Pentium Overdrive, and some other vendor's processors, based on the spec in Chapter 17 of the 1997 edition of Intel's _Pentium Processor Family Developer's Manual_ (order number unknown). I'm thinking about making a homebrew Pentium (P54C or P55) system, by which I mean, not using a purchased motherboard or an Intel chipset. #retrocomputing

Replies (2)

@brouhaha@mastodon.social 2026-07-22 04:26

Initially the only I/O will be a serial port or two, but I'll add an interface for an SD card if I can get as far as booting from flash into a monitor. Has anyone written an open-source x86 (386 or newer) 32-bit protected mode boot/debug monitor for bare metal? There won't be any secret motherboard/BIOS vendor binary blob code doing sneaky stuff in System Management Mode, and they didn't have the secret Management Engine (ME) crap back then either. #Pentium #x86 #boot #debug #monitor

Open ##4004710
@brouhaha@mastodon.social 2026-07-24 00:44

Four new-old-stock Amp 916557-3 ZIF PGA sockets, "Socket 7", for Pentium 75 MHz and up, Pentium MMX, AMD K5, K6, and others. One of the four, lower right in photo, is missing a portion of the top plastic, but I don't think that will affect its usage.

Open ##4058559