Storage typically comes in two sizes, 2.5-inch and three.5-inch . Most three.5-inch bays can accept 2.5-inch drives, however not vice versa (some 3.5-inch bays will have trays that are not designed for 2.5-inch drives, however they’ll nonetheless fit 2.5-inch bays). You can also see bigger bays in your case — these are for larger drives similar to optical drives and are usually situated within the front of the case, near the highest. Some coolers come with thermal paste pre-applied to the conductive material and some coolers do not. If your cooler does not have pre-applied thermal paste, you will need to manually apply thermal paste before you seat the cooler. To apply thermal paste, squeeze a small dot onto the middle of the CPU.