Uploaded September 2025 | Updated September 2026, 2 weeks ago

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The Macintosh IIsi was launched as a lower-cost alternative in the Macintosh II series. To keep costs down, Apple used more electrolytic capacitors, and the surface-mount electrolytic capacitors from the early 90s are past their expected lifetime. In addition, despite the power supply being made by Sony, the capacitors in it are also known to leak (though I can't help think "cost tweaking" by Apple led Sony to use lower grade capacitors).

I'm narrowing in on a possible area for faults: the ALS245 chips by the on-board memory. I noticed during an inspection of the board that there appears to be corrosion underneath. It looks like I need to continue investigation in this area by removing these chips.

Will we find trace damage under any of these chips? Will I put any on backwards? Will I manage to get rounded corners by the end of the stream? You'll have to watch to find out!

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Table of Contents
0:00:00 Pre-Roll
0:02:39 Greetings and Announcements
0:03:39 Wheel of Regrets™ (Who comes up with these titles anyway?)
0:04:02 Wheel of Regrets™: 8-bit TRIDENT TVGA8800BR 256K VGA Card
0:10:26 Wheel of Regrets™: IBM PC 5150 (the OG)
0:32:32 Dual Temper Tantalums!
0:33:25 Wheel of Regrets™: IBM PC 5150 and Trident TVGA8800, Continued Testing
0:56:45 It's In-IIsigh-nity, I Tell You, with the Logic Board from IIsi Number 1...
2:47:45 Discussing the Status of Logic Boards 1 and 2...
2:52:50 Closing Thoughts
3:02:56 Outro

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