PC turns on, CPU LED turns on mobo & then PC shuts off automatically - New Build . . . . . [SOLVED]

[Kelly42]

I built my first computer and when I turn on the power, it shuts down automatically. The CPU light turns on briefly, prior to shutting down.

Here are the parts list:

* Corsair Obsidian Series 750D Case
* Corsair Hydro Series H90 140mm CPU Cooler
* Corsair Vengeance LED 32GB (2x16GB) DDR4 3000 (PC4-24000)
* GIGABYTE AORUS GA-Z270X-Gaming K7 Gaming Motherboard LGA1151
* Intel 7th Gen Intel Core Desktop Processor i7-7700K
* MSI Gaming GeForce GTX 1070 8GB GDDR5

This problem has happened several times and I have reapplied thermal paste and made sure that the pins on the Motherboard, where the Processor is seated are not bent. Thermal paste was applied using pee method in center of processor.

I've plugged in a PC Motherboard Internal Speaker, and it does not make any beeps.

I have tried two different mobos (same model) and two power supplies (EVGA Supernova 750B2 and Corsair AXi Series, AX860i). I have also done the paperclip test on both and both PSUs are operating correctly.

The DDR4 are plugged into slots marked 1 & 2, as per mobo manual.

I have triple checked that all necessary cables are plugged in fully to both the PSU and mobo. I have also tried to boot up the computer w/o graphics card and hard drives.

All components excluding mobo, processor, and H90 water cooler were installed in another tower and functioned correctly.

Could this be a defective i7 Processor? Please advise.


UPDATE: I have also tried using Anarchy 8GB DDR4 2400 in slots 1 & 2, and also tried using a single DDR4 in slot #1 with the same result as above.

 

[tanckattb]

Have you ever booted into the BIOS/seen the Enter BIOS screen

 

[Kelly42]

No, the computer shuts down almost immediately after turning it on.

UPDATE: While the computer tower is unplugged, I removed the CMOS battery, held the power button for 15 seconds, put the CMOS battery back in place, plugged the tower back in, turned on the power on the back of the PSU and pushed the power on switch on the front of my tower. The result was the same, that the computer turned on for approximately one second (or less), and turned off again.

 

[Kelly42]

I've tested four different DDR4 memory sticks in slot 1 (Vengeance & Anarchy) and has the same result. I have tested the Corsair Obsidian 750D by using a screwdriver to bridge the + & - terminals of the power connector under the F_Panel connectors. The computer turns on and then after a second turns off.

I believe that the problem rests in the i7 7700k CPU processor, so I am returning the original and have a replacement on order. I will post, on this forum feed (sometime on or after Monday May 1, 2017), after I have seated the new CPU.

 

[Calvin7]

Thermal Compound Instructions for 7th Generation CPU is Vertical Line Method.
http://www.arcticsilver.com/intel_application_method.html#

 

[Kelly42]

Okay, so I have installed the new CPU and found that this was the problem. My previous i7-7700 was defective (even though no apparent damage existed with the naked eye). When I would boot up my computer with the defective i7 processor, all that would light up was the CPU led on my Aorus Z-270X-Gaming-K7 mobo.

Hopefully this feed will help at least one other person in the future

 

[Kelly42]

RELATED POSTS:

http://forum.gigabyte.us/thread/1079/starts-shuts-off-automatically-build
http://forum.corsair.com/forums/showthread.php?p=901280

 

[Lakken]

I had the same problem last year. But for m. It was my PSU that was faulty.
Strange actually, that you couldn't get into bios. When I build my first pc many year ago. I didnt plug the CPU in correctly, the pc stopped when the MOBO information came on screen, but I could go into bios...