The 68000 Dash 30fx, an Accelerated Mac IIfx

Most early Mac clones were built around 8-16 MHz 68000 CPUs or 16-40 MHz 68030 chips, but the 68000 Dash 30fx ran its 68030 at a blazing 50 MHz – 25% faster than the “wicked fast” Mac IIfx, which was the fastest computer on the market when it went on sale in March 1990.

68000 Dash 30fxThe Dash 30fx takes a 40 MHz Mac IIfx logic board, puts it inside a massive metal case to deal with heat and RFI issues (shown next to a Color Classic in this photo by Dave Thornton), and overclocks it to 50 MHz (the highest speed 68030 and 68882 chips ever made) – and sometimes 55 MHz, making it even more “wicked fast” than the Mac Iifx. In addition to a chipped IIfx motherboard, the Dash 30fx has front-accessible 5.25″ drive bays, which makes it possible to add an internal SyQuest drive, CD-ROM, etc. as well as internal full-height 5.25″ bays.

According to Applefritter, the back of the computer has a removable dust filter and “neglecting to clean this out causes the PSU to overheat and blow!”

According to an article by Marc Schrier, the only drawback of overclocking the IIfx motherboard was that the Processor Direct Slot didn’t work (or perhaps it did – but there were no 50 MHz PDS cards to plug into it, so nobodys know for sure). Schrier also notes that some IIfx owners have installed 50 MHz CPUs and managed to reach 60 MHz!

David Thornton, who provided the photos on this page, comments that the Dash 30fx weighed nearly 70 pounds and thinks it may have cost $40,000 when new. All of the ports are beneath the top panel for easy access.

Dash 30fx, rear view68000 Dash 30fxDash 30fx, front view with cover removed

Dash 30fx, interior


  • Introduced in 1990 or 1991, discontinued
  • requires System 6.0.5 to 7.6.1
  • CPU: 50 MHz 68030
  • FPU: 50 MHz 68882
  • bus: 50 MHz
  • performance: est. 8.5, relative to SE
  • ROM: 512 KB
  • RAM: 4 MB, expandable to 128 MB using both 4-SIMM banks of 70ns or faster 64-pin memory; can use 1 MB, 4 MB, 8 MB, and 16 MB SIMMs (the IIfx was the only Mac to use 64-pin SIMMs). Due to overclocking, the Dash 30fx requires faster memory than the stock Mac IIfx, which requires 80ns or faster RAM.
  • video: requires a NuBus video card – see our NuBus Video Card Guide for more information.
  • L2 cache: 32 KB
  • ADB: 2 ports for keyboard and mouse
  • serial: 2 DIN-8 RS-422 ports on back of computer
  • SCSI: DB-25 connector on back of computer
  • NuBus slots: 6
  • PDS slots: 1, inline with one of the NuBus slots, not usable because no 50 MHz 68030 PDS cards exist
  • size (HxWxD): 5.5″ x 18.7″ x 14.5″
  • weight: about 70 lb.
  • PRAM battery: 3.6V half-AA
  • Gestalt ID: 13
  • addressing: 24-bit or 32-bit


  • 68000 dash 30fx Photo Album, Dave Thornton. The most expensive Mac ever was also the fastest of its era – the 55 MHz overclocked Mac IIfx sold by Dash for US$40,000!

Further Reading

Keywords: #68000dash30fx #dash30fx

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