Hello,
My GPU is connected to slot no. 4(pic below) and it's running at x8, is there a way to make it run at x16 if it's not mounted on the 1st slot?

Unfortunately this is the way I've done it, since the GPU is mounted on the outside, and the PCIE x16 riser cable is not long enough to reach slot 1, and I actually like it that way since the cable doesnt have to reach all the way up and be even more visible.
It's no problem buying a longer cable and having it connected to slot 1 but I was wondering if it's possible to run it at x16 from the slot it is currently connected to.