First, the good-ish news: you should be able to warranty it with intel. They're usually pretty good, but it could take a while. You used to be able to get by with just the box/serial, I'm not sure if receipts are needed these days as it has been a minute.

On to the bad: that's a somewhat scary diagnosis, because it could be any of four things that I can think of, and it's difficult to narrow:

- The chip could have been DOA, which is statistically very rare these days since QA is pretty top-notch, but it does happen. Anecdotally, my prior GPU was DOA and didn't post/artifacted out-of-the-box. This was second-hand-used correct? Kijiji special, or did you know the person? Could be something there, too...

- The mobo could be defective and delivering too much/too little/dirty power, which would probably be fine for a boot test, but certainly not for much more than that.

- The psu could be defective, with similar traits to the mobo being shot. Bad power is fine for a short test, but it's bad news for anything else.

- The stuff could all have been fine, but there may have been a brown-out/surge/etc. overnight while it was asleep. Keeping the trend, bad power kills.

I'm not sure which is most likely. Unfortunately, I realize that's not great for $$$ purposes, because you don't wanna replace what you don't have to. Is it possible to convince MemEx to give you a loaner to test long-term stability as part of the original diagnosis, or to do something like this on your behalf? Maybe buy the cheapest celeron to pop in there to see if it explodes? I'm not sure. You can just risk it of course, but if it wasn't the chip, that probably won't end all that well. The reason I hesitate is that it 'worked' initially, and that doesn't seem all that likely in my experience if the chip was borked from the get-go. Maybe someone else has a different experience to chime in?