GPU Usage fluctuating Between 0-100% and Framerate and FrameTime spikes

[ForgottenMythz]

I brought My PC on the 1st of January 2020. However, since then, I wasn't really able to play games properly on the pc due to some problems recently. I have started playing heavy games on my pc and have noticed severe lag (I have posted a video exhibiting the lag). Link:- GPU usage fluctuating. - YouTube

The problem is that in new games(by new i mean like from 2015-2019) such as forza horizon 4, there are frametime spikes the Frametime just goes to like 100ms or higher and then there is fps lag moreover the GPU usage also fluctuate you can see the video above to see
this does not happen in old games like Ac black flag etc, but the new games like AC origins Mountblade 2 banner lord etc., there is so much lag making it unplayable my PC even meet the basic requirement to run these games, and I have watched YouTubers playing these games on same specs

I have run GPU benchmarks such as furmark and heaven benchmark they result show its ok
run the CPU (intel processor diagnostic tool) test that also say its ok
Run the ram test also, shows that ram is ok

MY PC SPECS ARE:-
CPU - I7 3770S
GPU- RX 580
HDD- 500GB (Games are running from HDD)
SSD- 128GB (OPERATING SYSTEM IS ON SSD)
Mobo- H61 Dual slot with USB 3.0 (but it is not connected
Ram - 8GB (4x2)
Power supply- 500W (sorry Idk the brand)

THINGS I HAVE TRIED

1. Reinstalling the windows
2. Updating the drivers ( i deleted them also, then reinstalled them)
3. I watched every video on the internet and tried what they said, yet of no use
4. Changed Power Supply also

I have attached MSI Afterburner Graph when playing games and details of HDD and SDD

hg

 

[Brian Boru]

I have posted a video

Why did you post the video a year ago, and only post here now?

 

[Foxhood]

Why did you post the video a year ago, and only post here now?

I'm also questioning how the PC was supposedly bought in 2020, yet has a I7 3770s.
That CPU was released in 2012, making it over a decade old now.

Which btw if this is a legit post. Would probably be the prime suspect for lag. You can't expect a 10y old CPU to handle (semi) contemporary titles without headaches.

 

[Brian Boru]

if this is a legit post

8GB RAM doesn't help either, especially when coupled with running games from HDD—there is likely a lot of swap file activity going on.

Does the RX have 4 or 8 GB of VRAM?