I didn't ask you to unsubscribe! I'm sorry if I sounded critical earlier, but it's not really wise to try offering help and advice until you have the laptop with you.
Ask the service place what stress tests they have run on the laptop and ask for a copy of the results. It's not really good enough for them to just say it looks fine, they need to stress it for some time to see whether there are any flaky components in there.
