Lagg spikes while gaming

[Eriquedesigns]

Hello, i've got a question

since this year, i keep getting huge lagg spikes in my games.

i'm running:
AMD Saphire R9 270x
AMD FX8350 (brand new, because i tought it was my CPU but after replacing it it still gave me lagg)
Asrock Extreme3
8GB kingston 1600

Description:
Whenever i play games (Think of: GTA V, The division, League of legends etc.) i keep getting fps lagg spikes. it runs it 60fps smooth, then after a while maybe 10 minutes it starts, it drops to 10 fps for 5 seconds. after that it goes to 60 again for 1 minute, then drops again.

Things i've tried so far:
Replace cpu component.
Update gpu drivers
Update Bios


Tonight i'll try to format my C: and disable my other HDD's to see if that helps and/if my windows is corrupt.

Any other idea's?

Thanks,
Eric

 

[Eriquedesigns]

My CPU usage drops, while the lagg is there.

 

[nibla123]

Very late answer but maybe the temps, thermal throttling?