[SOLVED] PC shut down, won't boot with graphics card pugged in

[Mr.Shark]

Hi, first of all i'd like to say that english is not my first language so go easy on me please. I've run into problem with my computer. I was gaming when my PC suddenly turned off. Ever since im not able to boot it. The only thing that happens when i press the power button is that my fans light up for a split second and that's it. When i press power button again nothing happens. I have to unplug pc from power outlet, wait for a bit or press power button and then reconnect pc to outlet. After this, my fans will light up for a split sec again. Othet than that, my PC is dead.

At first i was thinking it's the PSU, but i've bought new one and the problem did not go away. I've tried different solutions like reseting BIOS by taking out CMOS battery, checking if everything is really pluged in and so on.
The only solution i've came across is unplugging my graphics card from PSU. Once I do that, my PC will boot up. Sadly, i don't really have the option to borrow differnet GPU and given the prices I don't want to just buy one blindly. I don't even know if i could get one without waiting couple of weeks.

So my question is, isn't it possible that the problem is not GPU but for example motherboard? Is there any possible way how to check to be really sure other than trying different GPU? It seems weird to me that PC won't boot even into BIOS with GPU plugged in.

My specs are:
CPU: Intel i4790k
GPU: GTX 970
PSU: Corsair TX550M (Brand new one as I said)
RAM: HyperX 16GB (2x8) DDR3 1866MHz
Motherboard: GIGABYTE Z97X gaming 3
2 samsung 860 SSDs and 2 HDD by Seagate

Many thanks for any help.

 

[SkyNetRising]

Is there any possible way how to check to be really sure other than trying different GPU?

Remove graphics card from system and try with integrated GPU instead.

 

[Mr.Shark]

Remove graphics card from system and try with integrated GPU instead.

Yup when I disconnect GPU from PSU my PC boots up. I'll edit my original post to make that more clear. The thing that i was wondering is if it could be a MB problem for example. It seems weird to me that PC with GPU plugged in won't boot up even into BIOS. You don't need GPU for that so even if GPU is faulty, it should let me boot at least into BIOS no? I don't get even that far. My fans won't even start spinning.