New parts not working properly

[Dan1233]

So i've recently bought a bunch of new parts for my pc and installed them.
My problem is that my computer is running slower than before, now i cant even play "League of Legends" on low without lagging like hell (Ping fine) and some games it cant even start
which my old parts could easily at high settings.

i didnt make a clean windows install, but a half clean (The one where i keep pics and most of D drive)
i've tried installing newest drivers for everything.
But i cant' seem to find what is causing this, what would u recommend??

Specs:
New
Motherboard: MSI: Z170A Gaming m3
CPU: Intel i5 6600k 3.50ghz
Ram: ddr4 2x8gb 2133 mhz
Gpu: Radeon hd 7950

Old parts
Cpu: Intel i5 2300 (replaced)
Ram: 4x2gb ddr3 (replaced)
Gpu: Radeon hd 7950

 

[Ecky]

Check CPU and GPU clockspeed while gaming, see that they're clocking up to full. Check utilization % of both of these too.

 

[johnmanth]

Maybe for some reason cpu or gpu are downclocked, also try with one ram stick at a time

 

[Dan1233]

Check CPU and GPU clockspeed while gaming, see that they're clocking up to full. Check utilization % of both of these too.

I've updated my Windows and sudden it can open my games and play league, but i found out that im only using 10% Cpu, but i dont know how to check my GPU

 

[Dan1233]

Maybe for some reason cpu or gpu are downclocked, also try with one ram stick at a time

How can i check if its downclocked, and i will try that if my turns slow again