So, I plan on extremely upgrading my HP Pc, and i was planning on upgrading my Gpu mainly, but i needed a better power supply due to many manufactures mostly use 300W, and the main question here really is there any differences between a pre-built computers motherboard and one intended for pc building, like maybe mine is missing some things like fan slots on the board, that many you buy have.So far I ordered a case and a Psu, haven't arrived yet, however worst case ill just keep them till i get a new motherboard. Thanks in Advance.