Just documenting on my relay Opensource hardware, based on where I see Centralized Digital ID going.
Opensource Motherboard Firmware
Coreboot and Libreboot
Opensource Hardware and Firmware GPU maker.
https://github.com/adam-maj/tiny-gpu
TPUs Opensource Hardware/Firmware chips.
https://github.com/tiny-tpu-v2/tiny-tpu
CPUs Opensource
Hardware and Firmware Chips
vascofazza/8bit-cpu (74LS-based 8-bit MK1 CPU + bus system)
https://github.com/vascofazza/8bit-cpu
Full KiCad schematic + PCB (editable .kicad_pcb/.sch) 8-bit
https://github.com/fortinsylvain/MyCpu
Motherboards/Mainboards (AT/ISA Compatible or Classic Recreations) Opensource
Hardware Boards
M8SBC-486 (486 Homebrew AT-style Motherboard)
https://github.com/maniekx86/M8SBC-486
atx-286at-v1-mainboard (80286 ATX Motherboard)
https://github.com/rodneyknaap/atx-286at-v1-mainboard
Raemixx500 (Commodore Amiga 500+ Mainboard Remake)
https://github.com/SukkoPera/Raemixx500
OpenTendo / OpenTendo-TopLoader (NES Motherboard Recreations)
https://github.com/Redherring32/OpenTendo (front-loader) and TopLoader variant.
. Modern-ish Open SBC "Motherboards" (Linux-Capable)These are full single-board computers (essentially motherboards with integrated CPU socket/SoC).
icepi-sbc (Allwinner H3 Quad-Core ARM Linux SBC with DDR3)
GitHub:
https://github.com/cheyao/icepi-sbc
OLIMEX OLinuXino Series (Industrial ARM Linux SBCs)
GitHub:
https://github.com/OLIMEX/OLINUXINO (HARDWARE/ subfolders per board, e.g., A20-OLinuXino, A64-OLinuXino, etc.)RAM Opensource Hardware
For Retro / 8-bit / Discrete-Logic CPUs (MyCpu, vascofazza/8bit-cpu, RC2014-style):Z80-512K (RCBus/RC2014 compatible) —
https://github.com/skiselev/Z80-512K
For Retro PC
Motherboards (M8SBC-486, atx-286at, etc.):1MB 30-pin SIMM DRAM module —
https://github.com/hegars/1M-30pinsimm
72-pin SIMM template —
https://github.com/wiretap-retro/72-pin-SIMM-KiCAD-Template
For Modern-ish / FPGA / SBC expansions (icepi-sbc, OLinuXino, etc.):
Antmicro LPDDR4 Testbed / SO-DIMM style —
https://github.com/antmicro/lpddr4-testbed (and DDR5 variant)
HyperRAM / PSRAM PMODs (super easy 8–12 pin interface, no complex DDR routing):
–
https://github.com/mole99/qspi-pmod (QSPI Flash + dual PSRAM)
Amiga/Console Raemixx500 or OpenTendo):SukkoPera has open RAM expansions for Amiga 500/600/1200 (search GitHub SukkoPera OpenAmigaRam).
Bonus ultra-open options:
LiteDRAM (
https://github.com/enjoy-digital/litedram)
OpenRAM (
https://github.com/VLSIDA/OpenRAM)