Stutters

[Elessar199]

Hello everybody. I would like to ask for your help. I just assembled a new pc (except the psu) and I have problem with stutters (avg fps are 60 or above without v-sync, but 1% and 0,1% are about 15 to 19 fps max). My specs are: Cpu: Ryzen 5 3600, mobo: msi b550 a pro atx, Ram: Aegis G-Skill 16 gb ddr4 3200mhz (2 x 8), gpu: rx 6700 xt, ssd: Western digital SN 770 SSD 1TB M.2 Nvme PCI Express 4.0, cooler: Be Quiet Pure Rock 2 and the psu from my 2011 build, a Cooler Master Silent Pro 850 watt 80 Plus Bronze. The problem is that every game I tried stutters either on Ultra or lowest settings. The games I tried are: The Crew 2, Crew Motorfest, Star Wars Jedi Survivor, A plague tale Innocence, Valheim, NFS Unbound. The only games that work without a problem and with ultra graphics are Ac Valhalla and AC Mirage. I Benchmarked and stressed my gpu and cpu with 3D Mark and Kombustor but everything worked fine without any problems. Also the psu didn't seemed to have any problem during the tests. I also tried swapping to my old gpu (rx 580 8gb) after a driver clean uninstall with the exact same problems in the games. I also installed the latest mobo bios upgrade, closed all programs that may slow the pc like Xbox Gamebar, installed only the gpu drivers without the adrenaline app, disabled xmp and ran the games with my stock ram speed (2133mhz) put pc in performance mode, changed the virtual memory and finally I performed a format in case it was a software problem. Nothing worked. The first thing that comes to mind is the psu, but after consulting with a specialist though the phone he told me if the psu couldn't handled the power it would have caused crashes or black screen, or simply the pc wouldn't start. He was also baffled about what exactly was happening. I'm also at a loss and every bit of advice and help will be more than welcome. 

Thanks in advance.