fx 8350 gtx 780 or i7 4790k gtx 770

Solution
For gaming, the graphics card is normally the most important part.
But, the FX8350 is not in the same league as a 4690K.
And a GTX770 is reasonably close to the GTX780.

My take would be to build with a 4690K which will be good for a very long time and be superior where fast core speeds are needed. That is most but not all games today.

If one might be looking to triple monitor gaming or a 4k monitor, then a graphics upgrade to sli will be appropriate with either a GTX780 or GTX770.

As to the cards, I would look first to EVGA and not pay extra for fancy coolers or extra vram.
For gaming, the graphics card is normally the most important part.
But, the FX8350 is not in the same league as a 4690K.
And a GTX770 is reasonably close to the GTX780.

My take would be to build with a 4690K which will be good for a very long time and be superior where fast core speeds are needed. That is most but not all games today.

If one might be looking to triple monitor gaming or a 4k monitor, then a graphics upgrade to sli will be appropriate with either a GTX780 or GTX770.

As to the cards, I would look first to EVGA and not pay extra for fancy coolers or extra vram.
 
Solution
With the appropriate bios update, 4690K will run fine on Z87.
An oc to 4.0 should be easy without spending a bunch on liquid cooling.
How high you can go is dependent on how lucky you are in getting a good chip.
A vcore of 1.25 up to 1.30 is about as high as you want to go for cpu longevity. At that voltage, the heat generated is not excessive and can be handled by a decent air cooler in a decent case. Those investing big bucks in liquid coolers do it for one or two more multipliers or for bragging.
A 4690K at stock with turbo will not hold back any game. Consider any extra through oc as a bonus.
I would plan on a simple tower type air cooler with 120 or 140mm fans.
If that lets you get a GTX780 instead of a GTX770, you will game better.
 

A 4790K will cost $100 more than a 4690K in the us. For your $100 you get hyperthreading which id helpful for multithreaded tasks or games. For games, that is of minimal benefit.
You also get more l3 cache which is good, but I have no idea how to quantify the benefit.
The big reason is that you will get a better binned chip that runs at stock at 4.0 and 4.4 turbo all day long. OC is extra.
If you have the budget and the extra $100 is not that important to you I recommend the 4790K.

As to the graphics card, I like the GTX780 again if you have the budget. It is as good as it gets for gaming on a single monitor at 1080P. The R9 cards tend to run hot, take more power and generate more noise. They do tend to do a bit better in synthetic benchmarks than comparably priced nvidia cards. I see more unhappy owners of r9 cards on newegg feedback than the comparable GTX7xx cards.

 


You cant.
The GTX780 comes with 2304 CUDA cores, the GTX770 has 1536.
We all like something for nothing.
Graphics card vendors are wise to overclocking.
They bin their chips and use them in factory overclocked models that sell for some sort of price premium.
I do think you get fair value for the extra you pay for a factory overclock.

My canned rant on liquid cooling:
------------------------start of rant-------------------
You buy a liquid cooler to be able to extract an extra multiplier or two out of your OC.
How much do you really need?
I do not much like all in one liquid coolers when a good air cooler like a Noctua NH-D14 or phanteks can do the job just as well.
A liquid cooler will be expensive, noisy, less reliable, and will not cool any better
in a well ventilated case.
Liquid cooling is really air cooling, it just puts the heat exchange in a different place.
The orientation of the radiator will cause a problem.
If you orient it to take in cool air from the outside, you will cool the cpu better, but the hot air then circulates inside the case heating up the graphics card and motherboard.
If you orient it to exhaust(which I think is better) , then your cpu cooling will be less effective because it uses pre heated case air.
And... I have read too many tales of woe when a liquid cooler leaks.
google "H100 leak"
-----------------------end of rant--------------------------

I suggest a noctua nh-D14 or phanteks with dual 140mm fans.
Your pc will be quieter, more reliable, and will be cooled equally well