A:Answer If you are interested in a ram upgrade, there isn't much you should worry about. Replacing the 8 GB 2666hz with CORSAIR VENGEANCE 16gb (8GB x 2) works perfectly. Fans depend on the fan size, as some can definitely be replaced but things like the back-blowing fan on the left side of the case would definitely depend, while some others definitely could be replaced. Graphics cards depend, but you can definitely upgrade the graphics card, but make sure you measure the dimensions of the graphics card and make sure it fits before you buy a new one.