Gigabyte Z97X Gaming G1 WifiBK Boot failure

[Pegadroid]

My PC
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i7 4790K
Gigabyte Z97X Gaming G1 WIFIBK
2x8GB Gskill Triden-x 2400C10
MSI GTX 970
Samsung SSD 850 EVO 250GB
PSU Corsair HX750i
NZXT Kraken X61
=====================

after try to overclock i7 4790k to 4.6Ghz with Vcore voltage 1.200V (stable) then try to lowering the voltage to 1.150V after that my pc can't boot into bios and debug led error.
then try to clear cmos, unplug cmos battery, and issue is persist

https://youtu.be/fLgVKwG88_g

[dmdilks]

Have you tried to run the backup or bios 2? Your board comes with 2 switches for the bios.

[Pegadroid]

Have you tried to run the backup or bios 2? Your board comes with 2 switches for the bios.

yes, for bios 2 i can boot and normally.
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edit.
Problem solved
1. Shut off the power supply using the switch on the back of the PSU, wait 10-15 seconds.
 2. Press and hold the case Power On swtich, then while still holding turn on the power supply from the switch on the rear.
 3. Still holding the case power on switch, the board will start, once it does release the case power on switch and shut off the power supply via the switch on the read of the unit. (Do the latter two parts as quickly as you can once the board starts)
 4. The board will shut down.
 5. Turn the power supply back on using the switch on the rear of the unit.
 6. Turn on the motherboard by pressing the case power on button.

but when i try to Overclock again and fail, problem is back and can't solve with Clear CMOS.
i am using bios F7.
could this be the bios isue or hardware issue?

[shadowsports]

This is a BIOS issue, influenced by memory, CPU and how aggressive your OC is. 

I've talked with other users here in regards to our platform (Z97).  Thus far, all are disabling BIOS 2 via switch, and using it to recover (by enabling) if needed. 

Then there are users like dmdilks and myself who don't bother with OC.  You have 4 cores @4.0Ghz with 4.4 on tap.  Attempting a 200Mhz OC will give you <1% FPS improvement.  You'd be better off staying stock and tweaking boost, core and frame rate targets in Precision on the 970.  My 2cents 

[dmdilks]

but when I try to Overclock again and fail, problem is back and can't solve with Clear CMOS.
I'am using bios F7.
could this be the bios issue or hardware issue?

When you try to OC you put your CPU, Memory & MB into stress mode. What happens is you are locking up the MB. It is a feature that the MB has to protect itself. I do have to agree with shadowsports. One thing you could try is just use the turbo OC just to see what happens.

Get the computer back up and working and go over to the OC part of the forum ask what you are doing wrong. I have never OC in almost 20 yrs. The guys that OC can walk you through how to do it a little at a time. You could be pushing some of the setting a little too hard.

Plus when you do pull the battery and clear the cmos. You might have to leave it sit for some time like a couple of hours.   Plus this is just me and having nothing against any body that OC's. I myself think it is a waste of time.