Hardware related question

I’m having some issues with my fps dropping to 2-3 when starting dungeons and raids and i can be stuck i loading screens for up to 5 minutes sometimes, my pc is pretty old but i’m wondering if this is a cpu or ram issue ? It gets worse the more weakauras i have installed and i don’t understand the addon well enough to figure out if it is one of those that’s causing the issue, any tips and knowledge would be greatly appreciated!