Is there really an Art of Troubleshooting?

Well, we all have problems with our laptops and here's my recent journey of hopefully finding the right root cause for a screen not displaying anything. This is for a laptop from a highly reputed company under extended warranty.

Background

I ran a Windows 10 upgrade on a laptop and things looked okay initially until one day the screen went blank. thence started a sort of wild goose chase to figure out what went wrong. Multiple frustrating calls and chats with the support team (better not to name the company at this point) and below are the list of suspects, each of which looked so real that it felt like we may have the answer only to find it wasn't really the issue.

Suspect # 1: Screen display issue

as usual first suspect, it must be a screen display issue. Ran the diagnostic capabilities on the laptop in safe mode and it showed nothing wrong with the screen at that time.

Suspect # 2: Glitch with an upgrade

A search on Google gave multiple articles about how a glitch could affect screen displays. nothing worked among all the articles as everything looked normal as per those and the search continued.

Suspect # 3: Corrupted Windows Drivers or Windows installation

Got in touch with support and they asked me to boot the laptop normally and sometimes it would work and sometimes it would throw errors with random system files/ drivers. The support person said, its a software issue we can't help you. On prodding further he gave a suggestion which we tried next.

Suspect # 4: Corrupted Bootable USB drive

Trying to reboot from a startup (bootable) USB drive gave similar results as above and it really confirmed the support agents views that it was no longer a hardware issue but a software issue. i wasn't convinced though as I had booted using that USB drive earlier without any issues. In utter frustration ended the call.

Suspect # 5: Hard disk issue

After a few days of cooling off, called support again and this time the guy told me to run System Diagnostics and all tests initially seemed to work ok but would get stuck at the hard disk short DST (Disk Self Test) step (at 8 or max 14%) and subsequent step: Memory Test would also get stuck. It now definitely looked liked a disk issue because of which obviously the next test related to memory wasn't progressing. Shared screen shots as well but to no avail. For some reason, I still was unable to get them to send an engineer to check the laptop and give up yet again.

Suspect # 6: RAM corruption

Yet again, on another day, called support and this time the guy told me not to run System Diagnostics but instead to run Component Level Tests and this time all the hard disk tests pass in flying colors (100% pass). Feeling stuck on still having a blank screen, we finally decide to run the Memory tests and this time it gets stuck almost immediately at the very basic memory check at 1% and we feel we have found the root cause. Finally the support person agrees it is a hardware issue and decides to send an engineer in the next 1 or 2 days. I am hopeful I have seen the end of this.

Suspect # 7: USB port embedded in the mother board

On the anointed day a good 5 days later (vs the 1 -2 days promised), the engineer comes and checks everything and says you should have told them that this is a "No Power" situation and they would have assigned us immediately. I feel a bit wiser on how to handle this in the future.

He then slowly starts opening the case and says that there is a problem with the USB drive and since it is embedded it can't be changed. I am okay working with 1 less USB drive as long as the laptop works. He tries everything and says it looks to be a motherboard issue. I feel relieved. He however continues his detailed inspection like a junior Mr. Sherlock Holmes trying to find the elusive wire or piece that may be causing the blank screen. Then he drops a bomb shell:

"If your USB port was not damaged we could have easily got a mother board replacement, I am not sure if we will get one in your case."

That really got me thinking, would we agree to the stalled engine of an in warranty car not being replaced just because the door handle was damaged? To what level can companies really go to not take on legitimate costs?

I am still awaiting replies from them to see if this is the final root cause or will we go on another wild goose chase. Stay Tuned....