bapcsalesaustralia

So a while ago I managed to damage one of my GPUs fans (wifi card fell out of the PCI slot and hit the fan). Although still usable (and probably fixable), it struggles with a few of the games I play. I mostly play games like cities skylines and transport fever 2, and from what I can tell, I think I'm being bottlenecked primarily by a lack of 3D performance and dedicated GPU memory (both of those reach 100% in task manager)

I tried to ask the people at centrecom, but they told me I wouldn't notice any performance increases with an upgrade as my CPU and mobo aren't fast enough to notice a difference. But they never actually asked me what CPU or mobo I have, so I can't tell if that's actually the case or if they're just trying to get me to upgrade the rest of my components too. I'm new at all of this and my PC is a pre-built, so I don't entirely know what I'm doing in any case.

I currently have a Zotac GTX 1650 (4GB) but want to upgrade to an MSI RTX 3060 (12GB). I have an AMD Ryzen 5 3600 (6 Core) CPU and an MSI B450M PRO-VDH MAX motherboard. I checked compatibility with PCPartPicker and it seems everything will be compatible, and I do plan on upgrading CPUs and possibly motherboards eventually anyway, so upgrading GPUs won't necessarily be a waste of money, even if the rest of my PCs components can't make full use of the additional power, right?

Also, how do I go about checking space constraints? Is it just a case of taking a tape measure to the area around my GPU?

As I said I'm completely new at this and am not entirely sure I know what I'm doing... So any help is much appreciated!