I guess it depends on what you use your CPU for. If we look at IPC gains:
- IIRC, IPC increase from IVB -> HW ~ 8%
- let's assume 14% for Skylake and another 14% for Icelake (I used these higher values for an optimistic case scenario)
- let's also assume 2017 Icelake overclocks to 5.0Ghz and a decent OC on IVB is 4.7Ghz:
5.0Ghz / 4.7Ghz x 1.08 x 1.14^2 = 49% increase in speed by end of 2017
However, I can almost guarantee that the performance increase in games will be nowhere close to that, probably 10-15% on average against a 4.7Ghz i7 IVB. Look at BFG's average increase from a stock i5 3.3Ghz 2500K to a 4.4Ghz 4790K -
it's a mediocre 6% increase in games,
after 1 architecture with 14-15% IPC increase, ~700mhz-1.1Ghz increase in CPU clock depending on threading and HT. D::'mad: I can't see Skylake overclocking >1Ghz over IVB i7...
Unless there are a handful of games out there that you play all the time where you must have > 60 fps min (Crysis 3) at all times, Intel CPU upgrades for games now are basically more for fun/play with new OCing parts, but for performance increase for games, it's a waste of $.
OTOH, if you actually render, perform compute, etc. on your CPU a 5820@ 4.4Ghz will already be nearly 50% faster than an i7 IVB @ 4.7Ghz today.
I think with the state of PC games in the last 4-5 years, it's better to buy flagship GPU(s), larger SSD and a 21:9/4K monitor before even contemplating a CPU platform upgrade for gaming. Even with my 4-year-old 2500K OC, I would get way more performance from GM200 SLI/380X CF than Skylake @ 5Ghz. For that reason I am going to say that I am still undecided but leaning towards skipping the quad-core i7 Skylake. I would say on the top of my list a 500GB-1TB SSD, high resolution monitor and GPU upgrades sit
way above a CPU upgrade*. Just my 2 cents.
*Of course if I can get a smoking hot deal on some parts to upgrade to on the cheap, I'll do it just to play with newer parts. That's always fun. I guess I just have to come to terms that CPU upgrades in the modern times are not like they were in the past.