To gain access to the interior, simply remove the thumb screws holding each side panel in place. Even though the interior looks very similar to that of the Arc, there is one major difference. The CORE 3000 can hold up to six hard drives, while the Arc can take eight. Besides that the engineering is very similar. There is around 15 mm of space behind the mainboard tray, which is less than for the Arc which has 20 mm.
Taking a look at the hard drive bays, even though these can fit fewer drives, you still have the separate cage which may be turned by 90 degrees or removed completely to allow for extremely long graphics cards to be installed within the system. Once removed, the 140 mm, white bladed fan is clearly visible. It keeps the top three drives cool. Above that are the two 5.25 inch drive bays. The bottom one holds a metal frame so that you may use a 3.5 inch device within on of these bays.
Turning to the back of the chassis, the power supply will rest on four rubber "pyramids" to keep any vibration from being passed on to the chassis frame. The expansion slots - one of the core recognizing factors for the Fractal Design cases have been left unchanged and come with the afore mentioned white covers and black thumb screws. Above that you will find the 120 mm fan which pushes air out the back of the chassis. As is custom with all Fractal cases, the cables of the fans are sleeved.
A 140 mm unit pulls air out the case and out the top. It also comes with a 3-pin mainboard header and should still leave plenty of space for a large CPU cooler within the chassis. There is another opening for a fan on the floor of the chassis. This one tends to remain unused in most scenarios, especially since many longer PSUs will cover it partially. Before we dive into the assembly, let us take a quick look at the cables of the chassis. These are all sleeved with black tubing to go with the rest of the chassis. It is good to see that Fractal Design has kept all the small details with the budget line of cases.