Recently I've noticed large fluctuation in the performance of my PC during gaming, specifically on Overwatch and Dark Souls 3. My games "stutter" and movement in either game is very clunky, almost like input lag combined with the game moving like a second hand on a clock but in a "smooth" way.
I've been running Overwatch on ~medium settings (1080p). If I set the fps limit to ~100, the game is fine for the most part, until there is a lot of action of the screen, then my fps may only drop 5-10 dps from 100 to 95 or so, but I get the stuttering movement and the game is very hard to play. And if I set the fps limit higher to ~200, regardless of action there is immense fluctuation in fps, from 200 down to 100 and back up to 200 in about 2 seconds repeatedly, and then my PC turns off: straight to a black screen and off.
This is a fairly new problem and seems to occur no matter my settings, low or high/ultra, and with my specs I should be able to run the game flawlessly at high/ultra. My GPU temp doesn't exceed 90 C and my CPU doesn't exceed 65 C, which I'm aware is warm, but from what I can see there is little/no dust in there, fans are running, and as I say, this is only recent while my temperatures haven't changed drastically over the months.
I've tried to use HWInfo to look for problems, but with the fps limit at ~100 I don't see any drastic issues, and at ~200 the PC switches off. There's nothing relevant in the Event Viewer for Windows from what I can see. Perhaps the problem is voltage/amps? In which case I'm not sure what to look for, though the data is there on HWInfo.
My specs are:
CPU: Intel Core i5-6600
GPU: AMD Radeon RX 480 (8GB) (18.2.1 Adrenaline)
PSU: Corsair VS550 Series 80 Plus (Possibly the problem?)
RAM: 2x Crucial 8GB DDR4 2133MHz
MOBO: ASUS H110M-A/M.2
OS: Windows 10
Please help me, do I need a new power supply, or perhaps a replacement gpu?
