bottleneck CPU bottlenecking my rig

[BucK01]

My rig is being bottlenecked by my CPU, I ran task manager on a second monitor while playing and it was constantly maxed on my main game and I would like some advice on what I should upgrade to, my main games are Rainbow Six Siege, Destiny 2, And PUBG, however the game I was testing was Rainbow Six

 

Specs are as follows:

CPU: Intel Core i5 6600K overclocked roughly 20%

 

CPU Cooler: NZXT Kraken x41 liquid cooler

 

RAM: Adata XPG 16gb DDR4 2800

 

GPU: ASUS ROG GTX 1080 STRIX OC

 

Motherboard: MSI Z170A SLI Plus

 

PSU: EVGA SuperNOVA 850W 80 Plus Bronze

 

HDD: 2TB 64mb Cache 7200RPM 6.0GB/S

 

OS: Windows 10 Home

[BucK01]

2 minutes ago, lollipopjumper said:

to be honest though if you are only using it for gaming I don't think the bottleneck resulting from using that CPU is really significant enough to merit the amount of money you would have to invest to see a substantial improvement.

I am willing to get a new motherboard also I am considering going for SLI down the road so I personally do see the value and I think 8700K would be a good fit, thanks for the recommendation