Where to start with my broken ST?

[Badwolf]

Nothing looks to be screamingly obviously wrong. The clips are still in place on the PLCCs. That's a good sign.

All the memory resistors looks to be in place.

The only thing that catches the eye is one of the pins on the centre PLCC (MMU?) looks odd. Could just be that white crayon used on the tops carried a little too far?

IMG_20220810_184141.jpg

Next step would be power it back up (make sure the bottom's not shorted) and do the finger test on the RAM chips, as mentioned above.

If all else fails a copy of DiagROM/ST might be useful (the ROMs look socketed)? https://github.com/terriblefire/diagromst

BW

[aled]

That PLCC is OK as far as I can tell, just some of the white gunk (thermal compound? glue?)

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DiagROM looks useful, though I have no tools to burn ROM chips.

I will power up the machine and check the temperature of the RAM chips next.

[derkom]

OK, I worked it out eventually, need to shimmy the whole motherboard forwards to get the shield around the power switch.

For future reference, once you've removed the screws that secure the board onto the bottom case, you can remove the whole assembly as a unit, and then remove the top shielding and PSU after it's out of the case. Sometimes this makes things a bit easier.

[aled]

Not keen on having 240v within touching distance, so tonight's job was to butcher an old ice cream tub to hold the PSU.

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