Recently my gaming PC started acting really strange, with random black screens, BSODs, crashes and the rest of it.
To cut a long story of troubleshooting and testing short, it turned out to be that my GPU was drooping badly in its PCIe socket due to its weight and size. This wasn’t a problem when the computer was new, but now, a few years down the line, I suppose the weight and the added vibrations from its fans caused it to reach a breaking point, making it unstable.
Everywhere I looked around on user forums, people keep saying that a sagging GPU isn’t a problem and is merely an aesthetic problem. Well, I’m here to tell you otherwise; do not let your GPU sag. It can eventually bend your PCIe socket, and cause the connection to the GPU to break or become unreliable. This is especially true if you have multiple GPUs, seeing that not all PCIe sockets are built the same. (From my personal experience, the x16 ports that only have pins for x8 are less resistant to withstanding the weight of a large GPU.) A densely packed case with lots of cables can add to the weight and bend, especially if the graphics card is tightly fitted as it is, so watch out for that too.
If you have a drooping GPU, I’d suggest propping it up with something; there are several clever DIY solutions floating out there such as LEGO bricks, PVC pipes, fishing line etc.