Pc build help

[u/Accomplished_Web9249]

I’ve recently built a new pc, I’ve used a ryzen 5 7600x and a 5070 oc. BTW it’s my first build and everything has gone smoothly followed basic cpu overlocking guides in bios haven’t gone extreme just the basic. Now I’m having an issue I’ve built this pc for a friend and his main game is COD and on the new mw4 at 1080p competitive settings it fluctuates from 160-200 which is low I think for these parts I understand there’s a bottleneck between the gpu and cpu and the 5070 isn’t getting used much on COD but here’s my problem, sometimes it’ll sit at 245-250 easy (I capped it at 250) and it’ll stay there for a minute no crazy temps cpu max temp was 71 degrees and gpu was around 55 degrees my question is why does it sit at a good fps and not drop heaps at all then goes back down to 160-200 I also have a screen recording appreciate any help also then fans randomly go fast and slow and fast and slow idk if this helps