If the PSU seems the be properly supplying power to your components, with the fan properly spinning when needed and it not getting overly warm, then the PSU should be ok. If you are concerned about that, you can send it back to the manufacturer if it still has its warranty.
You can then move on to the motherboard, and begin checking if all its features work. Try checking if all your ram is responsive and that you're receiving the proper signals from your peripherals. You can remove your graphics card and check if your motherboard still works with just its on-board graphics.
Then to electronics: To me, a loud pop would be a sign of a failed transistor or capacitor, though more so the latter. On a motherboard, there are two kinds of transistors: polymer-based electrolytic capacitors, which look like a little, uniform color aluminum cylinder; and water-based electrolytic capacitors, which look like slightly larger, taller cylinders that have a shiny aluminum top and are wrapped in a black film. Because it seems like your motherboard is a more high-end motherboard, it most likely only has polymer-based electrolytic capacitors. Unfortunately, these are more difficult to check. You can inspect each one, checking if they're firmly seated on to the motherboard and that they aren't damaged or bulging. That's about the most you can do without having to remove parts and desoldering.
If you still have warranties to your motherboard or components, you could send them back and tell them your story, and that you think something blew. I wish you the best of luck, and hope everything turns out well!