Fx 6300 to a i5 4690k

Gaming PC

Case Corsair 780T
Cpu Amd FX-6300 , Stock Cooling
Gpu Amd R9 290 4GB
Mobo Gigabyte GA-970A-DS3P
Psu Silver Power 650W
Ram Kingston DDR3 HyperX 1600MHZ 8GB
Ssd Samsung 840 EVO 250 GB
Hdd WD Desktop Green 1TB

Is it a good improvement to go with asus z97a and a i5 4690k if i play a lot of arma 3, dayz and csgo?
Should i wipe the drive if i go with a new os? Because mine is oem so cant change mb without changing os.

in the games your are mainaly playing, you should get more stable and better minimum fps wenn you go with a 4690K yes.

You basicly dont have to whipe your drive, But i would personaly recommend it. If i´m right you can de-activate your current windows on your machine, and then activate it again after you did the swap and clean installation.

If you're going to buy the Intel CPU and MB outright (about 370USD total) you probably won't see a crazy FPS increase for the money. If there are stability issues with the 6300, then maybe a 8320 or 8350 would be worth looking at so you only replace the CPU and not the MB. The Intel would be worth looking at for programs/games that benefit from better single core performance and lower power consumption. If you're going to change the MB, it'd probably be a lot smoother to just backup your data, wipe the drives and re install the OS.

by good improvement, you just want to get rid of the minimum FPS stuttering?

I mean the i5 vs the 6300 isn't really comparable, the i5 kills it in every bench... and in those particular cpu-bound games, upgrading to an 8320/50 won't solve the problem... it's an expensive upgrade, but if those are your games of choice, an i5 will bring the FPS to balance... I don't think it's worth the money since you have a very functional build... but if the minimum framerate in those particular games annoy you that bad, then that WOULD BE the fix that I'd prescribe...

GA-970A-DS3P doesn't have that great of a power delivery.  You'd probably be looking at a motherboard upgrade if you want to upgrade to an 8 core.

That's not much of an upgrade, your going to be upset with the very minimal increase in FPS...just a warning

Most likely will barely notice the difference, when i went from 8350 to 4790k I only noticed about 5fps more.

in ARMA3? 

should be a LOT more than 5FPS in ARMA 3.... and it's not just topline FPS... it's the stability of the frames...

I upgraded and it gives a good boost in arma 3 but not that big of a difference in dayz, i still think it was worth it.