Sbeeer

Update:
The model is not G1 Gaming, it's the other one: GV-N970WF3OC-4GD
Still really good for the price, considering it's lower than reference models, even if the OC is not quite that good. However it does not have a backplate and that makes me sad.

It is your PSU.
I had the EXACT same issue 2 months ago, but back then I thought it was my motherboard. So I replaced it, and I still have the same issue if I allow my PC to go into hibernate.
I RMA'd my first CX600 2 months after I bought it. I am now on my second CX600 and I am going to replace it with an Xfx PRO650. I suggest you do the same before it potentially damages your motherboard as well. I found out the hard way that a CX series PSU should not be in a gaming system.
Luckily a PSU isn't hugely expensive, a new Gene motherboard is a whole other story. I had the Gene VI, now I am rocking a Gene VII. And I have no plans to let my cheap PSU kill that nice motherboard...
If you replace your PSU and you still have an issue, then it damaged your motherboard. I hope you still can RMA your mobo in this case.

Yours,for only $3000

If you're really interested in G-Sync, maybe just get a cheap monitor for now and wait for an affordable, decent G-Sync monitor later. Or maybe get the mod-able Asus one and hope the DIY kit drops in price.
 
I use that Asus VG248QE and I think it's fine, but I personally like the smoothness of high frame rate about as much as I like good IPS colors. It works out for me since I'm still playing through a lot of games that are a few years old, so I can get high framerates on them with my 780. Just keep in mind that not everybody can really tell the difference between 120 fps and 60 fps, so if you have a chance to see one in person, do it.

Dell is factory calibrated to 96%, definitely can't beat that 

The asus does have good color, for TN. Yet again it's not IPS.

response times that are quoted are complete bullcrap and and meaningless. You have to look at the overall input lag and not a single monitor manufacturer gives that number (because it's hard to measure and it would make a monitor seem worse). I saw the U2414H costs 300 Euro exactly on amazon Italy. If you want to save some money you should go with the U2312HM, which is pretty much just as good and is also great for gaming (low input lag and response time). 
 

http://it.pcpartpicker.com/part/asus-monitor-vg248qe

http://www.tftcentral.co.uk/reviews/dell_u2414h.htm

Any of the IPS panels you listed are solid options.

There are response test results in that page, its perfect.