[SOLVED] New built system only stays on for 20 seconds

Selannii

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Nov 16, 2019
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4,525
I just built my computer. However it will only stay on for around 20 seconds then power off then turn back on. Nothing shows up on my monitor. This has happened to me on another computer I built but for the life of me I can't remember how I fixed it.

System Specs:

GIGABYTE Z370 HD3 (Intel LGA1151/ Z370/ ATX/ M.2/ Intel LAN/ ALC892/ HDMI/ Motherboard)
Intel Core i5-8600K Desktop Processor 6 Cores up to 4.3 GHz unlocked LGA 1151 300 Series 95W
CORSAIR TX-M Series TX750M CP-9020131-NA 750W ATX12V v2.4 / EPS 2.92 80 PLUS GOLD Certified Semi-Modular Active PFC Power Supply
EVGA GeForce GTX 1060 6GB GAMING ACX 3.0, 6GB GDDR5, LED, DX12 OSD Support (PXOC) Graphics Card 06G-P4-6262-KR
Ballistix Elite 8GB Kit (4GBx2) DDR4 2666 MT/s (PC4-21300) DIMM 288-Pin Memory
ADATA SU800 256GB 3D-NAND 2.5 Inch SATA III High Speed Read & Write up to 560MB/s & 520MB/s Solid State Drive
Toshiba 1TB Desktop 7200rpm Internal Hard Drive
Asus 24x DVD-RW Serial-ATA
Cryorig H7 Tower Cooler
 

DMAN999

Honorable
Ambassador
My first step would be to ensure that the 24 pin and 8 pin cables from the PSU are fully seated into the connectors on the motherboard andon the PSU.
If either of those 2 main power cables are not fully seated the PC will not power up properly.
 

Selannii

Reputable
Nov 16, 2019
17
1
4,525
Thank you. I will check that out when I get home but I also think that I may need to re-seat the heat sink on the CPU. I think that may be what it is. Its the first time I've used the Cryorig H7 Tower cooler and its slightly difficult to put on.
 

Selannii

Reputable
Nov 16, 2019
17
1
4,525
No, its not just sitting on the case. I used the hardware that it came with. The problem I was having was lining up the screws with the holes on the cooler because they are partly obscured by the double fans. Then its adjustable on top of that.
 

Selannii

Reputable
Nov 16, 2019
17
1
4,525
Ok. So i made sure that the power supplies cables were plugged in properly. I re-seat the heat sink and it still does it. I re-seat the memory and the video card. Well, I had to pull them out to re-seat the cooler on the CPU. So, any suggestions at this point? Could the motherboard be bad?
 

Selannii

Reputable
Nov 16, 2019
17
1
4,525
I also wanted to thank every one that helped me. It’s still not fixed. I have an extra motherboard I am gonna try. But it might also be the video card. The monitor never showed the bios when I powered up the system.