So I built my first new PC in over 10 years today.
Some things have changed, some haven't.
First the interesting....Power supplies on the bottom of the case? How gravity friendly.

Keep the weight low and cords out of the way.
You can buy a case, ram, motherboard and video card in about any color you want. Pimp your PC. *shakes cane* back in my day you had the choice of black or off white for a case...and you'd like it! All PCB's were green...with the oddball brown ones. And the only lights you got were HDD and power buttons.
CPU's don't have pins any more? Woah. Funny how things change. They used to have pins. Then they went to a slot catridge. Then back to pins. Now it's a pinless design that you can't bend on accident.
After all these years they still haven't standarized the HD activity lights, power & reset buttons, ect into one idiot proof plug. You have single pin headers you need to consult a manual to figure out.