Should I upgrade with these? Help please!

[Azurenys]

Ok so, going to keep it sweet and short.

The current rig of mine is in my signature.

I've been thinking for a while that the CPU is bottlenecking me, since I've been getting fidgety 30 frames and sometimes like 5, then 50-60 again in GTA V at not even Ultra settings. I've read my GPU can do more than that and I know that my current CPU is kinda mediocre, even though I didn't plan on overclocking and it was marketed as "the best cpu if you don't wanna OC for your buck".

So I've been thinking of getting:
Intel Core i5-4690k 3.4GHz (3.8GHz Turbo Boost)
8 more gigs of 1600 RAM

and MAYBE 97 MOBO even though my current one can perfectly support 1150 and the new i5 CPU, so kinda not sure about that.

also might switch my case to NZXT PHANTOM H440 as my current one is very basic and not very dust proof/quiet. Can remove lower HDD bay to fit the CPU.

Also worried my PSU might not be powerful enough for the upgrade, is there truth in that?

What do you think guys?
Obviously, rig is for games at 1920x1080 res only as I don't do videos/drawing programs.

[fixx]

No point, 4690k is about 15-20% faster than your current 4440. Your FPS problem is clearly elsewhere.

Make sure video RAM usage is below 3GB (turn settings down) in case you're suffering from the GTX970 memory issues.

[Azurenys]

From what I know, if it's around or below 3.5GB it's fine, and I'm at around 3.1GB.

Maybe it's the "only" 8GB RAM? :/

[fixx]

From what I know, if it's around or below 3.5GB it's fine, and I'm at around 3.1GB.

You could try go clearly below 3GB just to test it out. Various benchmark sites show you should be able to run 1080p ultra with GTX970 just fine.

Maybe it's the "only" 8GB RAM? :/

Nope. Unless you have something on the background using up all RAM like chrome with 50 tabs open.

[Azurenys]

Yeah, my bad actually, as the problems I have with the game are with it's Online version, not single player.
Also found out many others with different setups have similar stutter issues.

Still, should I go with the upgrades or wait/skip?