Question Pc won’t boot no matter what

[nwomo]

hello so I am putting together a custom pc and no matter what I do it will either not boot or just not turn on please help more info below
specs…
Motherboard:HP 655842-001 655581-001 HP Z220 CMT WORKSTATION MOTHERBOARD
Cpu:i5 3570
Gpu:GTX 560
Ram:8GB DDR3
Psu:550w
when everything is plugged in the pc will not power on but when I unplug the gpu power from the power supply it turns on but no boot
When I try a different working gpu it turns on but no boot what is going on please help me
So here is everything I have tried
Reset cmos
Reseat ram
Reseat gpu
Try different gpu slots
Try different ram slots
Try ECC ram

 

[EyyMunchian]

What is the other working GPU that you test with?
What is the model and how old is your PSU?
Do you know if your motherboard is hardware locked at all?
Try booting the system with no GPU and your monitor connected to the board using the iGPU on your cpu.
Whats your ram config? 2x4? 4x2?1x8? Try using only one of your ram dimms on bootup, sometimes my system boots but doesn't post because of a faulty ram stick.
Let me know on your progress.

 

[nwomo]

What is the other working GPU that you test with?
What is the model and how old is your PSU?
Do you know if your motherboard is hardware locked at all?
Try booting the system with no GPU and your monitor connected to the board using the iGPU on your cpu.
Whats your ram config? 2x4? 4x2?1x8? Try using only one of your ram dimms on bootup, sometimes my system boots but doesn't post because of a faulty ram stick.
Let me know on your progress.

I have a APEVIA 550w captain power it’s new
I just got new ram still won’t post
Tried only one stick still no post
I tried using intergrated graphics still no post