First thing I would do is clean the VCC pins (red/black plug) and check if there is voltage there being supplied

TheMLGladiator wrote on 2025-11-27, 02:35:

I finally got my hands on a complete and mostly working socket 7 system in an AT-style case. The only issue I've found so far is […]
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I finally got my hands on a complete and mostly working socket 7 system in an AT-style case. The only issue I've found so far is that the case MHz display doesn't seem to light up. Here is the back of the display for reference:

The attachment PXL_20251126_152138800-EDIT.jpg is no longer available

It looks very similar to this one (but not quite the same): AT Computer Case MHZ frequency LCD display

Does anyone have any ideas on isolating which components are bad without having to desolder everything? Or what the other headers are for on the board?

Looking at the design I'd say you have 2 possible situations:
1) no power - check the voltage on the incoming power lead as the previous poster mentioned. If that's good check the big diode.
2) whatever IC2 is under the potting compound is fucked and the whole board is fucked by extension

So basically it's either a really simple fix or you can throw it in the trash can 🤣

Forgot to post an update. I wasn't paying attention and I'm pretty sure I accidentally shorted the pins next to VCC while the board was powered. There was a spark and now the display works perfectly.