For sale is a rare Sonnet Technologies QuadDoubler BST-40F processor accelerator for the Apple Macintosh Centris 610.

This is the 80/40MHz version of the QuadDoubler, using a full Motorola 68040 processor with integrated FPU running at 40MHz. Although the board is marked "605-610," period Sonnet documentation indicates that this 80/40MHz version was produced specifically for the 20MHz Macintosh Centris 610 and Workgroup Server 60/20.

The QuadDoubler installs directly into the Macintosh CPU socket in place of the original 68040 processor and doubles the processor clock without occupying a NuBus or PDS expansion Technologies QuadDoubler

BST-40F version

Sonnet 80/40MHz designation

40MHz full Motorola 68040 processor

Integrated floating-point unit

Direct CPU socket installation

No accelerator software required for normal operation

Compatible through Mac OS 8.1 according to Sonnet documentation

This card has been fully tested in an Apple Macintosh Centris 610 and is working properly.

Please verify compatibility with your particular Macintosh before purchasing.

Please see the photos for the exact item and cosmetic condition.

Fast and careful shipping from Tokyo, Japan.Please be aware of any customs import duties or taxes in your country.
🇺🇸 US buyers: shipments are sent DDP (Delivered Duty Paid), which means there are no duty fees on delivery, as duties are included in the shipping rate.
Please also note that customs delays may occur, particularly within the EU.
This is vintage hardware/software for vintage computers. Use of this item requires era-appropriate knowledge and compatible hardware/software. Please carefully verify your intended use and compatibility before purchasing. I am happy to answer reasonable questions, but compatibility with every system or configuration cannot be guaranteed, and step-by-step installation support is not provided. Issues arising from incorrect installation, modification, or incompatible use are outside the seller’s responsibility.
I usually ship within 24 hours. If shipping falls on a Saturday in Japan, dispatch may occur the following Monday.