Tag: 20mhz

2 matching upgrades

Showing 2 products.

StatusProductWhat it doesCompatibilityLinks
Sold outChecked Jul 24, 2026GZ/80S 20MHz CP/M Cardby GGLABS
z80cpmapple ii slotcoprocessor20mhz512kreplica

Runs PCPI Applicard-compatible CP/M software on a dedicated 20 MHz Z80 with 512K of onboard RAM.

The GGLABS Tindie store was taking a break on 2026-07-24, so no current order could be placed. This card is PCPI Applicard-compatible, not Microsoft SoftCard-compatible; choose CP/M software and disk images for the Applicard environment.

Sources
  • Apple IIe Exact model
  • Apple IIgs Exact model
Vendor product pageOfficial project documentation
DiscontinuedChecked Jul 27, 2026Rapidus 65C816 Acceleratorby Sebastian "Candle" Bartkowicz / Lotharek
65c81620mhzacceleratorfpgasdramflashinternal upgradesolderingvintage

Replaces the Atari 8-bit CPU with a 20 MHz WDC 65C816 accelerator backed by fast SRAM, SDRAM, flash, and software-selectable modes.

Both Lotharek hardware packages are discontinued. The 800XL package includes two Adaptus boards and requires CPU and OS ROM removal, socket work, a correctly oriented ribbon cable, and EXTSEL, MPD, and ground connections that differ between Freddie and non-Freddie boards. Its page says replacing DRAM with the separate SRAM module is mandatory and records additional O2 timing workarounds for Ultimate 1MB. The XE package may need four or five precision sockets to clear the cartridge slot. The official Rapidus PDF remains unavailable to automated extraction under WF-001, so obtain complete documentation before installing a used board.

Sources
  • Atari 800XL Exact model
Lotharek Rapidus for 800XL archive pageLotharek Rapidus for XE archive pageSearch eBay for Atari Rapidus