New build reboots after 20 seconds - no post, no beeps

[simo9002]

Specs:

PSU: Super Flower Golden Green 550W
CPU: Intel i5 6500
Motherboard: Gigabyte H110M-S2H
RAM: HyperX Fury 1x8gb DDR4 CL14 2133MHz

My new build reboots after 20 seconds and loops. CPU fan works, motherboard led works. Fans work if I plug them in. I don't think it's a power shortage as the system stays on for 20 seconds and doesn't shut off immediately.

Tested already:
-Checked all cables, and yes the CPU 8 pin cable is plugged.
-Took all components off from the case, I have the motherboard laying on a piece of cardboard.
-Tried another PSU, with it the system stays on but no post and motherboard led doesnt work.
-Tried using the new PSU on the old pc, and it booted normally.
-Reset CMOS.
-Switched RAM sockets and tried booting without RAM, same issue.
-Checked motherboard for bent pins, didn't find anything.
-Started without case power button by connecting the two power sw pins.

I didn't use an anti-static wrist band, but grounded myself by touching case/psu constantly. At first I wasn't that careful, but it's fairly humid where I'm building it so static electricity doesn't build up much at all here. However I'm not ruling out this possibility.

It definitely seems like something is using way more voltage than it should so the PSU shuts the system, but what would cause that? I think the problem has to be either the motherboard or the cpu. Is there any way to determine which one of them is broken?

 

[Themastererr]

Specs:

PSU: Super Flower Golden Green 550W
CPU: Intel i5 6500
Motherboard: Gigabyte H110M-S2H
RAM: HyperX Fury 1x8gb DDR4 CL14 2133MHz

My new build reboots after 20 seconds and loops. CPU fan works, motherboard led works. Fans work if I plug them in. I don't think it's a power shortage as the system stays on for 20 seconds and doesn't shut off immediately.

Tested already:
-Checked all cables, and yes the CPU 8 pin cable is plugged.
-Took all components off from the case, I have the motherboard laying on a piece of cardboard.
-Tried another PSU, with it the system stays on but no post and motherboard led doesnt work.
-Tried using the new PSU on the old pc, and it booted normally.
-Reset CMOS.
-Switched RAM sockets and tried booting without RAM, same issue.
-Checked motherboard for bent pins, didn't find anything.
-Started without case power button by connecting the two power sw pins.

I didn't use an anti-static wrist band, but grounded myself by touching case/psu constantly. At first I wasn't that careful, but it's fairly humid where I'm building it so static electricity doesn't build up much at all here. However I'm not ruling out this possibility.

It definitely seems like something is using way more voltage than it should so the PSU shuts the system, but what would cause that? I think the problem has to be either the motherboard or the cpu. Is there any way to determine which one of them is broken?

Usually shutting down after a certain amount of time is either heat/voltage limit issue.

You cleared the CMOS using the proper procedure correct?
-Remove all cables
-press power button
-remove battery,
-short pins located at southeast corner for 5 seconds,
-replace battery and try to boot?

If that doesn't help, you've gone through most of the steps needed. I would ask a local shop to test components for you. Have them show you that it does not work, don't take their word for it.

Also try re-seating your CPU.

 

[simo9002]

I cleared the CMOS once more, but this time I waited a whole hour to replace it. Now the system stays on, but still does not post and there is still no beeps to be heard.