Product Showcase - Interior
Actually there are many rubber grommets for cable management everywhere, so cable routing ports have rubber inserts, again for that clean look. To your top left, the placement for three optical devices like DVD-ROM etc. The motherboard tray has a nice large cutout behind the CPU socket to help you with back plate installation for larger CPU coolers.
You'll find plenty of tool-less drive trays that will support 3.5 drives ready to be inserted into the chassis. Installation of the HDDs is really easy. You can place them into one of the 3.5" drive trays by slightly bending on each side to create additional room for the drive to fit into. Once on the tray the hard drive is locked in place with four pins that fit into the screw holes on the sides.
You can also mount SSDs on there, with screws though, Just align it with the four holes at the bottom and slide it into the plastic retention clips. This way each tray can hold one HDD and an SSD, quite clever.
Then just slide them into the drive bay and at the rear side you can connect them and route cabling.