Motherboard dying or bad?

[JellinWellen]

So recently I've had this issue whenever I turn off my computer or put it to sleep. Whenever I put it to sleep and try to wake it back up all I hear is a "click" echo from somewhere in the case and my computer just shuts off. Same thing if I try to power it back on after turning it off. The computer will then refuse to boot up at all unless I completely unplug it from the wall, which allows me to boot it with my GPU in. (rocking the PSU switch off and on doesn't work and the PC still won't boot). It does not do this if I unplug the GPU and use the iGPU for some reason. I have tried this with a 980ti and a 780ti with no change. I have also replaced the PSU (750G2 with another 750G2) as I assumed that could be the culprit, again there was no change.

When I first built this PC I had issues with the motherboard (Asus z170 Pro Gaming) and I basically couldn't do anything as programs and browsers would stutter and not work, so I had newegg send me new one which fixed the issue. Now that these pro gaming boards have been out a while I see so many bad reviews on them, should I try to RMA with Asus and get a new one?

 

[JellinWellen]

There is also a loud electrical buzzing noise coming from what appears to be a cluster of capacitors on the motherboard towards the bottom. This is when the GPU is under a high load.