Haha...go for it I say... but to utilize that much horsepower one would have to go 4K or your crazy tripple monitor setup...and Id be worried about investing in such limited VRAM at that point to be honest.

Single GTX 780 @ 100% performance and 3GB VRAM - perfectly ok

Dual GTX 780s @ ~170% scaling performance and 3GB of RAM - ok today but getting close to the limit of VRAM

Tripple GTX 780s @ ~230% scaling performance and still only 3GB of RAM - just asking for VRAM trouble in a year or two

And once you add overclocks...there really is no point of having close to 200% more GPU horsepower of a single GTX 780 and the same amount of VRAM IMO.

I'm not sure what are the problems people have with AMD's drivers. Back when I had my HD 4830, they worked just fine. Right now I'm using a GTS 450 since I got it for free, and I clearly can't see any difference in the drivers department between AMD and Nvidia.

Geforce 780's have 3Gb per card (At-least here anyway, never seen one with less!). So from a games point of view, even with 3x geforce 780's it will see 3Gb in total.

Noise and Heat aren't a problem, just throw it all under water. :)
Otherwise, it's really not that much noisier than a single card, you could always make your own fan profile so that the noise curve is lower anyway.
But generally look for cards with 3x large fans as they are generally not as noisy and don't ramp up in noise compared to say... A blower air cooler like what's found on AMD's reference cards.

I game in 1080p and my 7970 has used over 2GB a few times, and people playing BF4 Alpha have reported ~2.2GB of VRAM used in just 1080p.  Honestly I wouldn't buy any card stronger than a 7970 unless it has 4GB of RAM.

Hence IMO the 780 should have 4GB (Especially since the damn thing costs double a 7970 and only mildly outperforms it), and the 770 should have at least 3GB.  

But has their ever been a time Nvidia hasn't cheaped out on RAM?  1.25GB GTX 570 anyone?

There isn't a damn thing wrong with AMD drivers.  I have owned and do own cards from both camps and I can tell you that overall neither has superior drivers.  The only things I would say are:

-Do a clean install of AMD drivers every time.

-Don't download Nvidia drivers the second they come out because there are frequently BIG beta bugs.

Fully agree... There are some Nvidia cards that have offered enough VRAM for enthusiasts, but they are never reference designed by nvidia. Someone that got a custom GTX 580 3 gb sli in early 2011 for example is still rocking almost any game at max at 1080p and can do surround as well at medium to high settings. While someone that may have bought 2 reference cards i surely hitting the 1.5 gb vram limit.

This leads me to the gtx770 4gb versions. I honestly think they are the best bang for the buck right now. They get all the features of a nvidia 700 series gpu(gpu boost 2.0, nvidia shield support...), but run the optimized drivers and scaling of the 680 cards since thats the gpu they are based on. With 7ghz GDDR5, that can be overclocked more, it makes up for the 256bit bus and high resolution gaming. And at 429, they are good value too...

You know for all the talk about Nvidia's drivers being so much better than AMDs, since I switched to Nvidia with a 560 Ti I have had nothing but fucking driver problems. I have literally never had so many graphics driver issues. There has been 4-5 driver releases that have constant TDRs when using a web browser or if the system is left idle for too long FFS. The current driver branch is a fucking train wreck.

So how well do you think that would do with a 4K display?

Well. If you are running at 1920x1080 with a single GPU, then AMD is fantastic.

However, dial it up to Eyefinity-levels of resolution with 2-4 cards and then it's an entirely different arena completely, there is still frame latency issues (Which will be fixed next driver release) and AMD typically lags behind nVidia in game profile support (I just make my own profiles.)

However, to be realistic, nVidia and AMD's drivers have more lines of code than what exists in the Windows Kernel, they're that complex, hence you are bound to have issues crop up with that many lines of code, if you really, I mean really want poor drivers, look no farther than Intel. AMD and nVidia's drivers are gold plated in comparison!

Well, another option is of course AMD with 6Gb 7970's, heck even though my cards are only 3Gb I can still out-bench Dual Titans and the 3 cards only cost as much as a single Titan!
Of course Triple or Quad Titans leaves my cards in the dust, but price/performance wise I couldn't be happier.

Depends on the game. For 4k I wouldn't get anything less than 3x High-end cards, I'm running close-to 4k resolution pixel counts and it's demanding as it is, which is probably why the next generation consoles are only 1920x1080, not enough GPU horsepower that's affordable yet!

Meh maxwell aint powerful enough for me I will wait for Volta.