I'm in a strange position where I can't really afford anything and don't need an upgrade as 4ghz on the Pentium is plenty fast for doing the pretty much nothing I do at the moment (surely will overclock further too, haven't really tried) but at the end of the day it's still a dual core.
If prices are going to drop or even stay the same I'm happy to wait but if they're going to go up I should buy something now. I've looked at cheap i5 S and T models (low TDP but mobo will override that) and equivalent xeons but hadn't really considered the high end ones as four threads still isn't really that future proof and the price difference on first glance wasn't that much. Looking today a 4670K or even 4690K is about half 4790K so you probably have a point - I should have asked a week ago before payday, prices will no doubt be higher for a week or two. Glad there's no rush!
If you are doing it before the end of the year, the 4670 is a good upgrade that will tide you over for a while so you can save up to get a more modern board and chip.
It's not meant to be the only upgrade for the next 5 years for you, it's just enough to tide you over.
If you are going to try and get something slightly better, and a motherboard as well, no. It's a poor choice because the costs are too high for what you get compared to the longevity. You would be better off getting something even newer, though I don't agree that a quad core is not future proof enough. We only just got 6 core I7's this generation, yes, they are awesome, but Intel is backtracking on it to a degree (no hyperthreading on the 9700k, wtf?). Worse still, more cores does not equal speed. I have an 8700k running Linux, and while some things really do work better with it and I can do a TON without bogging it down, a lot of cores sit idle a lot of the time.
A high end processor today runs almost any program fast, with or without multi cores, so extra cores just let you do more at the same time. Most people get that part, what most do not realize is that the hardcore stuff that could REALLY benefit from multi core tasks, like 3d rendering and video editing, doesn't take good advantage of it. It's not a programming issue, it's a problem in how the programs fundamentally work, you can't have frame 2 render before frame 1and still maintain a proper timeline. Maybe in the future, but not currently and it will require a massive rewrite of many of these programs to really be able to make it work. This is why the 18core processor is actually better for use in Premier than the 32core, it has less cores but a higher clock. While I blame Intel for not pushing more cores, the truth is, they just don't do as much as people think, so while Intel may be right in not pushing them, I also think Intel purposely held back the market in order to just cash in.
Again, my advice, get you a good I5 to hold you over and enjoy it. It's a relatively cheap ($100) compared to an I7 board and chip combo, which will run you closer to $350. For $350 you can buy a brand new board and I5, so why bother with something 4 generations old? Yes, you would need ram, but it's far more future proof than spending $350 on a 4 year old combo that will again need updating soon. Because what is really going to hurt you in terms of future proof is not the core count but the PCIE revision, USB type, and M.2 slots.
