Disk 1 (D:) 100% active time laggy as hell

[SpiritFreak]

Recently, my HDD started and is still freezing 24/7.
This problem occurred about 1 month ago and I fixed it by disabling Superfetch, Window Search and windows notifications. But now that it's back, I have no idea what to do.
I can still use my PC as fast as it should be by unplugging this secondary drive (only using the main which is an SDD) but I have almost 100 GB worth of data on the malfunctioning HDD, and I cannot afford to lose it.

If you're wondering, the HDD is a SATA 2TB drive st2000vm003-1ct164

 

[Illyria]

Download CrystalDiskInfo link: https://osdn.net/projects/crystaldiskinfo/downloads/65980/CrystalDiskInfo7_0_4.zip/

It will show you the health of your drive.

You should know what to do after that.

 

[SuperSoph_WD]

Welcome to Tom's Hardware, @SpiritFreak!

I'd follow @Illyria's advice and use your HDD manufacturer's brand-specific diagnostic utility to check up on the health and SMART status of the drive.
Make sure you backup all your important files from the HDD somewhere off-site ASAP! If it influences the system's performance in such a way, the drive could be failing. Another thing you should definitely try is swapping the SATA cable and the SATA port where the HDD is connected to the motherboard and see if that will improve its behavior.

Hope these help you! Keep us posted with the troubleshooting!
SuperSoph_WD