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Atari 520 STM OEM PCB Mother Board with Rainbow TOS 1.4 New Tested
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Atari 520 STM OEM PCB Mother Board with Rainbow TOS 1.4 New Tested
Price: US $125.00
Atari 520 STM OEM PCB Mother Board with Rainbow TOS 1.4
New Complete and Boot up tested if you request.Not sure why Atari made these??
Rainbow TOS 1.4 was produced way after the 520STM was out of production. Atari must have had a special order for the 520STM main boards with Rainbow TOS??? The 520ST was the first ST released by Atari in 1986. This is a later revision Mother Board REV E and includes the RF modulator for NTSC TV output as well as composite video out and the TOS 1.4 EPROM upgrade done by Atari. This was never sold in the case as far as I know.Most of the chips are soldered. The 68000 CPU is soldered which makes this mother board more reliable than the socket ed ones Atari produced in 1986.The GLUE, MMU, DMA. Video Shifter and 6 chip TOS are all socket-ed in the main board I opened to takes pictures of.The RF Modulartor with a few other components can be de-soldered and used to upgrade a 520STF/1040STF to STFM versions.These are new complete mother boards that we power up test to insure they boot to desktop.
If you want them sealed and not test we can sell them that way but then will not warranty that they work. We guarantee they are brand new and complete with Rainbow TOS 1.4.
All brand new parts.Picture 5 shows 3 versions of the TOS 1.4 labels. One version does not say TOS 1.4 and has a different part number on them. The other 2 versions say TOS 1.4. I have no idea why Atari used different labels on the same TOS versions. Later when the TT was released Atari renamed TOS 1.4 to be TOS 1.04. This has caused some confusion with users but the official Installation instructions and the TOS itself says TOS 1.4. The TT used 3.05 and 3.06 so for some reason Atari changed how they numbered their TOS versions.
Pictures 1-7 are of the mother board itself, picture 8 is in the 520STM case that is sold in a separate sale. Case NOT included in this sale. Pictures 9 show a Box of 8 new Mother Boards and picture 10 is several new factory sealed boxes of 520 STM mother boards.
If you want a full case never opened buy 7 and we will ship 8 sealed mother boards.The 520ST and 520STM used external power packs and disk drives. These are not included.
"If you do not understand something about an sale then PLEASE
contact us and get an answer you understand before purchasing. NOW CHARGES FEES ON SHIPPING AND HANDLING.
WHEN YOU BUY MULTIPLE ITEMS AND PAY BEFORE WE SEND A COMBINED INVOICE YOU MAY PAY A LOT OF EXTRA SHIPPING."

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