Question Fluctuating frametime

[SnowmanCS]

Just got a new build, been experiencing major frame time fluctuating, going from .9 ms or 1 ms to 100 ms or 50 ms out of no where.
Happens on the whole system doesn't matter if im gaming. I think it might be my PSU causing a problem somewhere, but what ever it is can you answer what it is?
Cpu:Ryzen 9 3900x
Mobo:Meg x570 Godlike
Gpu:rx 5700xt nitro+
SSD: Hynix 1tb
Ram: (2x16)32gb ddr4 3200hz corsair vengeance rgb pro
PSU: KCAS 1200W Bronze cert
Monitor: Acer Nitro VG272 Xbmiipx 27", up to .1 ms frametime

 

[yut0ng]

same problems here. 3800x and 5700xt