After having Windows 10 reinstalled as part of a repair process in a PCBox repair store, my PC is slow enough to be almost unusable. These are my specs:
OS: Windows 10 Version 1903 Build 18362.418
MB: 970 GAMING (MS-7693)
CPU: AMD FT(tm) - 8350 Eight-Core Processor, 4200Mhz
GPU: NVIDIA GeForce GTX 1070
RAM: 1x8GB 2x4GB
SSD: One 250GB SSD where the OS and little more is installed.
HDD: One 1TB HDD where the rest of programs and files are.
The PC worked perfectly before taking it to the repair store, except for the monitors losing video from time to time. I took it there to have that problem fixed, and two days later I received it back. Supposedly they simply fixed a faulty connector and did a fresh reinstall of Windows 10 on my C drive (The SSD). The video problem is gone, but since then the PC is completely unusable. I've read that after a fresh install you need to give windows time to reinstall updates and everything, and like the ignorant caveman that I am I decided to leave it on for a whole day and night, around 26 hours in total, and then restart it to see if that fixed the problem.
Of course, it didn't. The PC is still slow, to the point where while I was able to play games like Arkham Knight perfectly well with videos, spotify, or discord in the background, sometimes leaving a MOBA open by accident while starting another game and not even noticing it, now I'm having problems running Streets of Rogue alone. Windows Explorer lags, this forum takes almost thirty seconds to load, and as I am writing this the text lags and freezes.
I've tried a few things people have recommended me, like disabling heavy programs at startup, activating my MOBO's OC Genie, resetting window's index and reseating the RAM and CPU cooler in case they weren't installed properly, but nothing has worked.