Crash every few minutes with flickering patterns on screen

Thanks! My reasoning was that since the exact same (or extremely similar) issue has been seen on three different laptops, with different logic boards and running both MacOS and Windows, it would almost have to be something to do with the CPU/GPU itself, not the system around it.

There is nothing out of the ordinary that I could see on either the logic board (e.g. blown capacitors) or the heat transfer tube, though the tube I haven't been able to inspect on its bottom side yet. The SSD is removable but uses an Apple proprietary connector, so not possible to swap or to run tests on without buying adapters.

As thermal paste seems to be the only thing I'm able to do (or willing to spend money on for such an old laptop), I'll probably have to try that.

@jay82379 - What are you running on this system (and the others)? Maybe you are over stressing them.

These older systems can easily be driven into the ground like a horse. While horses are built for running, they can be pushed to their limits, potentially leading to death from exhaustion, dehydration, or heart problems if not properly cared for and rested. Running heavy CPU and/or GPU based games or other programs can be the root cause here.

I don’t think that’s your issue at this point but after repairing the cold solder joints I think you’ll find the problem will be gone.

As far as the SSD, you can use an external drive to test that. It just needs to be setup as a bootable drive and setting it as the boot drive.

Well the strange thing is, I pretty much don't need to run anything at all to make it crash. Happens just as well if I boot into recovery mode (cmd-R) and just let it sit there idling.

Good point about using an external drive. Unlikely to be the cause though, as the crashes can happen regardless of disk activity – which anyway could likely not cause GPU or kernel level issues unless through corrupting swapped-out memory, and that can't really be happening in idle state either – but probably still good to test after ruling out other possibilities.

Today I tested letting it run in cold weather outdoors for closer to an hour (no crashes). So looking more and more like either a thermal paste or heat pipe issue.

@jay82379 - Don’t discount a cold solder joint!

Certainly not! But in any case not the first thing to try (and not worth paying for on a laptop this old). The gradual worsening has my hopes on a simple thermal paste issue.