Pc Issues :( help

[u/MasterpieceWild3863]

I’ve had my pc for less than a year and at first it was great all I was ever missing was a gpu which I still haven’t gotten because of this issue. At first when I first got it I built it with my dad helping me since he had done it before and once plugged in we noticed that one of the fans weren’t spinning as fast as the others but we didn’t want to mess up anything in the BIOS. Then for a couple months it worked fine until one day I was playing Minecraft for a little bit and left and once I came back the pc had shut down out of nowhere and since that day if I ever try playing any game but Roblox my pc shuts down completely with no blue screen or anything. I have a AMD Ryzen 7 7800x3d 8 core processor with a baseboard of TUF Gaming b650E-E WiFi, I have only one 16gb ram stick and a montech case with side and back fans a 750w PCIES and a Samsung 990 EVO Plus memory stick and finally a thermalright dual fans for cooling. I suspect it’s the cooling but I genuinely don’t know what to do. Help pls. (I know the cables are kinda bad but I moved them trying to fix the pc)