You reinstalled the OS. If drivers weren't installed after the fact, problems indeed can occur with limited functionality of the devices like the GPU, but under no circumstances should you be getting a BSOD, even when you are not using the GPU with its driver (but the Microsoft Basic Display Adapter). Not all BIOS manufacturers label their settings the same, nor do all the motherboards have the same functionality. The power states depend on your PSU as well. Certain PSUs did not support certain power states on Haswell CPUs a few years ago.
If there are no yellow exclamation marks in the device manager, then the drivers should be ok:
How to Open Device Manager in Windows 10, 8, 7, Vista, or XP
My point is, the drivers, when installed, should mostly work okay. By mostly, I mean that there are very few exceptions with buggy releases, but that's a rare sight.
I'm just confused, if you said that sb had replaced the HDD, the monitor, why didn't that person try out the rest of the components until they figured out what is broken. I can only do some much here and I am almost certain that this is some kind of a hardware failure. I cannot guarantee that your RAM/mobo/video card are good because I don't have access to spare parts nor to your computer to test them out. It would be best to take it to a shop and have it properly diagnosed and see what else (if anything) is broken in order for you not to spend money on parts that you may not need after all.
Here is the GPU test, but be
very careful if trying to run it alone, because it can damage your GPU if the temp gets too high.
FurMark Display Card Stress Test