I would wager EarthDog has spent about 1000x the amount of time you have on research and has quite the repertoir of knowledge at this point, so please don't argue with him and shoot down everything he says. If he tells you AMD has an advantage at 4K because of bus width, it's because AMD has an advantage at 4K because of bus width. Not because he's pulling that information out of where the sun don't shine.
I know that this GPUs are very close to each other. And definitely I'm not taking this from nowhere.
I've been using R9 290X for a year already.
My impression - It's freaking hot brick. I have stock cooler on it. It's extremely noisy but also efficient.
The fan curves are set up in MSI AB. So basically I try to keep core temperatures in 65-70c, vrm has the same temperatures.
It's freaking noisy! I'm playing only with headphones. And this is only 1 GPU.
We are talking about 2 GPUs with NOT stock cooler but aftermarket 3-fans Gigabyte edition.
I'm not trying to talk like a teacher here.
Do you know how much heat radiates this ****? )
It will be at least 500w of heat-power inside a case + CPU overclocked to 4-4.2 which radiates about 130w.
The one should need to install 7-8 120mm fans (about 1500rpm each one) to unload all this heat from the case. So it will be pretty noisy PC.
While with 970Gtx we will have at least 200 less heat inside of the case.
Where I'm wrong? )
P.s.
I've told already - 2x R9 290 will be like option in this config. People ask me to build Intel + Nvidia rig.
P.p.s.
Don't even start about FSP Aurum. ) It's very good PSU and I love it. Coil noise - yes.. sometimes, but it worth it's money.