For sale is a Macintosh LC575 logic board fitted with a 33MHz 68LC040 CPU, specifically prepared for the Color Classic “Mystic” upgrade.
The board has been carefully cleaned, professionally recapped with tantalum capacitors, and hardware-modded for use in a Color Classic (no software modifications required). It is in excellent working condition.
RAM (36MB Total) and VRAM are included, as pictured.
The hardware modification involves removing resistor R116 and adding a resistor at R109, allowing the board to boot correctly in a Color Classic without requiring software-based hacks. The board has been tested to boot into System 7.5.5 and is capable of running later compatible versions of classic Mac OS as well.
This is a plug-and-play Mystic upgrade for the Color Classic when installed correctly.
Please note compatibility carefully: this board is suitable only for the Macintosh Color Classic, Color Classic II, or Performa 275. As it has been hardware-modded for the Color Classic, it is no longer suitable for use in an LC575.
Does not include PRAM battery.
Photos are of the actual board being sold.
A compatible 3D-printed rear panel for Mystic Color Classic configurations is available separately in my store.

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.