What are these STe modifications?

[Pacman]

I was recently given my dad's STe, which I had added several upgrades and fixes to while he had it.
That was probably 30 years ago, and now I'm scratching my head as to what they are....

The first one involves a 74LS164 which appears to be piggybacked to U211 (74LS04) and has wires going to U203 (MC68901), U202 (AY-5-8910) and R110 (4.7K). My guess is one of the many serial port modifications for allowing higher speed modems. Could that be it?
The PCB and coin-cell battery next to it, and with the TOS ROMs on top is a real-time clock. I also replaced the DMA chip, hence the IC socket.

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The next one is a lot simpler -a single wire between U504 (LF347N) and U508 (LMC1992N). I have no idea what this might be. Any ideas?

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[czietz]

Nothing special. Both are factory bodges, as can be seen on other mainboards, e.g., here: download/file.php?id=3374

As far as the first one is concerned, this exact question has been asked and answered multiple times already:
viewtopic.php?t=5603
https://exxosforum.co.uk/forum/viewtopi ... 191#p60191

[frank.lukas]

... original Atari factory hardware patches see the Atari STE schematic

[Steve]

I love how this exact same question gets asked at least once every couple of months We should gather together all the separate forum posts about it and put them in one mega-thread just for fun

[Pacman]

Ah! Thanks for clearing that up.
Looking at it I thought to myself how ugly a DIY job I had done back then. Fortunately it wasn't my doing at all and I was wondering if I should remove it to clean things up
Thanks for confirming.

PS: I noticed that the motherboard of this STe was different from my other STe (which didn't have any of these factory bodges), so they must have been incorporated into newer revisions of the motherboard itself.

I love how this exact same question gets asked at least once every couple of months We should gather together all the separate forum posts about it and put them in one mega-thread just for fun

Sorry, I had no idea this was asked before, or even that it was a common thing (I was sure it was something I had done myself).
Yes, it would be useful to have this as a sticky. Titled something like "Atari official factory modifications".