Problems with new budget gaming build

[omgshinoda]

hello.
i built a budget gaming rig for my girlfriend, and it seems to have some problems. (no, not my first build)

The Symptoms
- Windows update is having error (win 10)
- Windows troubleshooter does not work
- Windows app store works sometimes, and doesn't
- System restore points disappear
- Certain apps from app store disappear
- Got Critical Process error on restart aka bsod

What i have done so far to alienated the problem
- Multiple fresh re-installs from genuine windows 10 cd 64bit
- Reinstalled from different cd drive (that works fine on a different computer)
- Reinstalled to different ssd and hdd (that works fine on a different computer)
- Reinstalled with different ram that works fine.
- Reinstalled from another genuine windows 10 CD but with same serial from before

Whats most annoying is, the problems comes and goes. Sometimes things that doesn't work, randomly works/stops working.

PC Spec
- MSI Z97 PC Mate LGA 1150
- Intel Core i5-4590 Haswell Quad-Core 3.3 GHz
- ASUS GeForce GTX 960 STRIX 4GB
- CORSAIR Vengeance 8GB (2 x 4GB) 240-Pin DDR3
- Kingston SSDNow V300 Series 2.5" 120GB
- WD Red 2TB NAS Hard Disk Drive
- RAIDMAX HYBRID 2 RX-730SS 730W

Any help will be appreciated.
Could this be from faulty motherboard/cpu?

 

[JingLuci]

Might want to try a different CPU for starters ? Since you've already changed so many different component no harm trying with another CPU.