If it's got a boot disk failure, how the hell can there be nothing wrong with it?

That was all done during "repair". They checked every component of the machine, in terms of hardware it's in A+ condition.

What goes for the OS, I ran it through system checks and all that fun stuff and it keeps telling me it's all right. Which just keeps baffling me because something has to be off if the damn thing doesn't boot properly. I had issues with the thing before, with windows booting up but then insta-freezing or throwing me a blue screen and the machine flung a corrupt boot manager at me before, too. Now it refused to even boot window, however every time all results say that there should be no issues because everything works as intended.

It's also starting to get a rather expensive "nothing's wrong with your machine". Counting the three incidents I had, where all my knowledge of fixing things (including searching for help onlines ect) reached it's limits and I brought the thing in to get it checked, that's a total of over 300 bucks by now. Too much money for nobody finding anything wrong with the computer.

I am that close to throwing it out the window.

I ran into an issue similar to this with my current rig, although it's been far more reliable for myself.

In the end, the solution I found was to clean out the interior of the case and components with canned air - spraying off all the dust that had built up. Apparently said dust was causing the issue for my computer, as it worked perfectly after cleaning its insides.

Not much to offer in terms of technical advice, but here's to hoping it can get resolved soon or has since resolved itself.