Gaming pc cant run games right even at their lowest settings after windows reinstall

Yes

just reinstalled

Okay I'll try this thank you

Okay so I tested out using my on board Intel hd 4000 graphics and i cant really run any games but it seems like right off the bat the problem is better which is worrisome. I now am recalling something i forgot that could have something to do with this problem, a little before i did the windows reinstall, like a day and a half or so, I added a 4 gig stick of ram to the already 8 gigs i had installed. To make room for me to put the ram in I took out my graphics card and when everything was finished I forgot to plug in the power supply PCI-E cables back into the graphics card, and turned back on my pc with it only connected into the motherboard like an idiot (I was a little drunk, even though I knew its a bad idea to work on something like a custom built pc while under the influence of alcohol, I was just trying to install 1 stick of ram so i thought it'd be a walk in the park) It made a weird sound like a repetitive quiet clunking and I immediately noticed, turned off the pc, plugged the cables in and then turned on the pc again. Could this have done irreparable damage to the gtx 970? I remember playing games after that and they all still ran perfectly till after the reinstall of windows, but could it have caused a slow working malfunction or problem with the gpu that i only noticed after the update because it had slowly gotten worse? If so is there anything i can do moving forward to fix the graphics card? Or is this situation probably unrelated to my issue?

Okay ill try that. And are you positive not having the pci power cables plugged in couldn't cause any problems like the card overheating or something? when I said I "immediately noticed" the issue after the pc was on with the gpu only attached to the mb, it couldve actually been like 3-5 min or a little more I'm a little fuzzy on how long exactly it was on before i noticed it, I just know i fixed it pretty quickly, but anyways I'll try running some games and stuff with the new ram stick out and see what kind of performance I get.

Yeah I went back to my original 8 gbs of ram and the problem was unchanged. I don't have a spare good gpu to test but i do still have 2 years left on my warranty for the card so looks like I'll probably be getting a replacement. Thanks for the help.

MERGED QUESTION
Question from stoneconndor : "Gaming rig not running games right. choppy, blurry, and ghosting lag in every game, even very low-spec games"

specs: geforce gtx 970 ftw - i5 3570k - 12gb ram - 750w psu - Gigabyte GA-Z77X-UP4 TH - 1tb hd - 250 gb ssd
So for the past few weeks or so my pc has not been performing well with any games. It's like there's a slight lag constantly even when I'm getting good fps, and looking around in games is choppy and blurry and just looks kinda headache inducing rather then smooth and this happens in all games, even low spec games like minecraft. In addition to this when I'm playing rocket league about every 2-3 matches or so or every like half hour of playing my screen will flash a blank beige or dark green screen for 5-10 seconds and when it goes back the game is extremely laggy, like every slight movement is choppy as hell. This is only resolved by restarting the game but then i still have the issue of the slight constant annoying lag. Rocket league is the only game where this screen flashing problem happens for some reason. In pubg, which ran great at max settings a few weeks ago, every preset even very low causes lag, and when running or looking past a window sill, door frame, or side of the building it ghosts incredibly bad, I can see the line of a white window sill for example repeat itself and ghost in front of itself like 20 times causing the whole window to be filled with its ghost image, and it takes like 2-3 seconds to fade. I've changed nothing about my pc in the past few weeks except installing 4gb of ram to my previous 8 and that seemed to go smoothly and cause no problems, when i was installing the ram i accidentally bumped my graphics card slightly but it was not anything that you would think could cause damage just a slight bump. I also accidentally turned on my pc without the power supply cables plugged into the graphics card, but then noticed immediately and turned off my pc to plug them in. Also i reinstalled windows 10 and the problem started right after that, but i don't see how this could have caused it because since then I've done about a dozen windows reinstalls (switching between 10 ultimate, 10 pro, and 7 ultimate) and installed all the right drivers and shit over and over. At first I thought it was my graphics card but I'm not too sure anymore because I've done tons of tests and it benchmarks great and seems to have no issues, and its only 1 year old. So after that i thought it was my pcie slot so I tested with my built in intel hd 4000 graphics and in the games i could run the problem seemed to be completely gone, like in minecraft looking around looked smooth and normal again, and in pubg, even though I had zero chance of ever running it with built in graphics, in the loading screen a weird glitch that popped up at the same time as the other problems where my characters forearms had blocky noticeable shadows moving around them was gone. After this I moved my gpu from my x16 slot to my x8 slot and oddly this made a lot of the issues better for a day or so and then they slowly got worse again. In pubg the ghosting went away but the lagging on all settings was still there, albeit it was better then it was before but it slowly has gotten worse again somehow. Same thing in rocket league, no lag or screen flashes when i first booted it up with my gpu in the new slot, but after a day or two of playing every so often it was back to the same as before flashing and everything. I can't think of anything else really that could be causing the issue, my power supply has had a weird high pitched whine when the pc is off but not powered down all the way for a year or so, and at the same time the problem developed or a little bit after my 1tb hhd that I've been usiing since 2012 started to fail noticeably, it clicked and hummed and made weird revving noises, but I just unplugged it to use only my ssd and the problem is still present, thats the only things I can think of. I guess its likely it's a graphics card issue, I have 2 years left on my warranty for it so I'm thinking of just sending it back for a replacement. But before that I would appreciate any help from people who know more then me on if this could be a problem with another component of my pc, or any tests i can do or things i can look at to narrow down the problem. Thank you.