I can't really say much for render farms or anything like that, but from a pc gaming perspective, I agree with the sentiment check said regarding the cpu. And get a decent GPU (graphics card). I just recently sent back my gtx780 in order to get 1 or 2 gtx770 myself after checking how much more I would get for my money. My CPU is a relatively old one for some standards, but a very well known in the Over Clocking community, the i5 2500k. There really isn't much point for me to upgrade it as things stands today, other than the GPU.
I never had the 920, but from what I remember it was a good buy at the time for OC'ing. As a rule of thumb I think in 'these terms' in regards for gaming rigs, cheap overclockable CPU's, paired with more expensive GPU's. Since it's on the GPU side there is more performance to gain. Some kind of i5 as check mentioned sounds great. Unfortunately I haven't checked the current SKU's(models) to give an exact recommendation, since I know my i5 2500k is all thats still needed for current games. I've OC'ed it moderately at 4.2ghz. But most ppl I talked with pretty much just set it running at 4.5ghz right from the start without almost a hickup, and from what I recall the line lies about 4.2 where further OC requires increased Voltage... But this wasn't supposed to be about my CPU though, just to give some glimpse how easy it can potentially be and illustrate the point of saving money on the CPU side.
And just in case your not already familiar, the K at the end of the model number on Intel CPU's means it's unlocked, so people who plan for OC goes for them for that reason.
Without checking online for others feedback and experience, my thoughts by default drift towards the cheapest unlocked i5 (ending with a K)
As to all the other stuff, rendering ect, it's not my field and I have no insight other than that CPU power matters more, and perhaps more importance of parallel computing. So I'll hopefully leave you in better hands in taking advice from other people than me on that.
Oh and yeah, the MB is x79 which is socket 2011, and that means in case you don't know that you cant even use the i5 on it which is socket 1150. Dropping the x79 and the i7 for some z87 and a i5 can save you money and pretty much match what i7 and x79 can do, and relatively speaking even surpass it. But you are forced to like buy a x79 socket 2011 if you just have to have the 6-core extreme CPU which costs a ton of money and doesn't give you anything extra gaming wise. Thats one difference between the two platforms to mention something. Take a look at how the new haswell i5 scales in BF3:
The results above is with a gtx680 btw and stock speeds. The top CPU is a 6-core i7. Notice my "old" 2500k right behind the current gen i5. And don't be fooled by synthetic tests when thinking about gaming, cause they will show you a whole other result than you will experience in practice when playing games.
Ah your going to play bf4 ...I've made plans for that too, we better play some together then ! I've been kinda starved to not only play something, but with someone. Maybe this Autumn I will finally get to do it.
In summary: if it was me right now, well first of all I'd do a lot more research emh, but as is right now I'd get the i5 4670k, a z87 board, and probably a gtx770. But thats me, get a 2nd opinion on it is a good thing, and remember I've just given a rough idea of what I would probably do, or how I would begin to think as a baseline while perhaps looking into further details. I haven't looked into the performance/price ratios for where you might absolutely get the maximum amount of performance for every penny or anything in depth.
