Question gpu performance issues (fps stutterring)

Jan 9, 2020
Hi, this is my first time posting about this technical stuff, but i really need you guys help with a few questions,i'll try and be as concise as possible, the issue really amounts to two basic points:

OK this is basically the gist, my rig just turned 4 years old this October, i am a proud owner of a strix gtx 970, and yes i know its an old card, and that was precisely the reason why i decided to try overclocking it, having never done anything to it prior,so i read about it and watched a few videos, and finally i had a go at it. this is my current setting(picture) View:

i did the trial and error with both the clock speed and memory speed, and tested it with valley benchmark and although i didn't leave it running for the recommended 15 min, i did leave it running for about half that time and saw no artifacts and no crashes, but i then compared my speeds, and they were all considerably higher than most OCs of people with the same card, so i thought that was strange but since i didn't experience any crashes or artifacts while gaming,i overlooked that aspect, this was a month ago.

2) On a second kind of unrelated note, before ever overclocking the gpu, i had a highly annoying problem, i never had any other issues with my rig other than this one, and when i took it to the shop where i bought it, he would format the pc and the problem would go away...for a while until it normally re appeared, and this has happened around four times since i have the rig. The problem is: while gaming the screen would freeze for an instant,like a hiccup,randomly and then immediately after the game would resume normally, and this happened cyclically and randomly, while i was monitoring this situation i noticed that the gpu would spike abruptly down to 0 or close to 0, and then rise up to normality right after. i mean WTF is causing this xD? its been 4 years, and every time this happened i would take it to formatting the windows and the problem would disappear for a long while, but then it would resurface with the passsing of time . I really need your help on these questions....

The strangest thing just happened, as i was trying to show by recording the issue, it stopped happening.... the game where this was most ocurring was jump force, i found a clip where it happens, but usually that happens all the time in the lobby. at the 0:36 mark of the video, it starts, the aforementioned stutter or freeze:


here is the benchmark of my rig: , i really hope you can help me...

Thank You for your patience