[SOLVED] Computer extremely slow. reboot fixes the issue. sometimes

[mimen2]

Ever since I bought my PC 3 years ago I had this problem, though now I finally had enough.
When I boot my PC, one of the following may occur:

1. All is normal.
2. No monitor output whatsoever.
3. I log into windows and everything is super slow. Opening a browser takes ~10 seconds.

I ran furmark and got ~10 FPS on a 1920x1080 test.
When all is normal I get ~100 FPS.

Ran the Intel processor diagnostic and passed in modes 1 & 3.
Specs:
gigabyte z97m-ds3h
GTX 1070ti (previously had a GTX 960 with the same problem)
Intel i7-4790

Any ideas how to debug would be appreciated.

 

[NightHawkRMX]

drive and ram configuration?

 

[mimen2]

128 GB SSD (ts128gssd370s)
1TB HDD (wdc wd10ezrx-00a8lb0)
8GB RAM

 

[NightHawkRMX]

Make sure the ssd is not full. Keep 20 or so gb free.

A full ssd can degrade performance. I have even had a system refuse to do anything after the desktop loaded due to a full ssd.

 

[mimen2]

I can't believe that this whole time this was my issue. And I can't believe you found it so quickly!
Thanks a lot!!