Could you check the PSU again please, try to make a clear photo of it, that'll help a lot 
I doubt this is complete or I'm understanding it wrong, but if I understand it correct and the 126w is correct then your PSU isn't enough to power your system as it can't even give enough to power the CPU and GPU when they are idle let alone the rest of your system. Then your system wouldn't even power on, it might attempt it a few times but nothing more after that.Sunon DC12V - 126W.
My Computer
At a glance
Windows 10 Proi5-650016GB DDR4 2133 Crucial Ballistix Sport LTMSI GeForce GTX 1060 GAMING X 6G
- Computer type
- PC/Desktop
- Computer Manufacturer/Model Number
- Custom build
- OS
- Windows 10 Pro
- CPU
- i5-6500
- Motherboard
- Gigabyte B150-HD3P-CF
- Memory
- 16GB DDR4 2133 Crucial Ballistix Sport LT
- Graphics Card(s)
- MSI GeForce GTX 1060 GAMING X 6G
- Sound Card
- Intel Display Audio
- Monitor(s) Displays
- Liyama ProLite XB2483HSU-B2
- Screen Resolution
- 1920 x 1080
- Hard Drives
- Crucial MX200 500GB & Toshiba DT01ACA300 3TB
- PSU
- Corsair RM550x
- Case
- Fractal Design Define S
- Cooling
- Cooler Master TX3 i
- Keyboard
- Func KB-460 (MX Red)
- Mouse
- Corsair Gaming M65 RGB
- Antivirus
- Bitdefender Total Security 2016 + MBAM Pro + MBAE Pro
- Browser
- Google Chrome
- Other Info
- Creative Sound Blaster Tactic3D Rage V2 headset
