To access to the interior, simply pull the side covers off. As they are held in place by small pins, you won't need a lot of force or any tools to do so. Lian Li has kept the interior layout clean and open to allow for maximum compatibility, but don't let the simplicity fool you as everything is pretty well thought out with openings perfectly placed to allow for clean cable routing. Looking at the backside of the motherboard tray, you will notice that the forward section offers more room for cables but is also meant to hold an SSD which mounts inside the chassis. Smart decisions by Lian Li when it comes to openings all around the motherboard ensure that you can not only hide excess cables nicely but also reach and connect hard drives fairly easy—even with the system filled up.
In the front section of the TU150, the aforementioned 120 mm fan mounting possibility is pure and simple, while the area to the side of it takes the same simply approach but with much more functionality. As the enclosure is pretty compact, the only compromise you need to make is to use an SFX or SFX-L PSU, which is mounted with the power connector facing the side of the case with the air vent of the solid panel. Below that, you can clearly see where one of the two 2.5" storage drives can be fitted.
The trend of simple but effective continues in the rear with the three PCIe slots, each of which is covered by a reusable cover above which is the second opening for a 120 mm fan. The mounting holes have been elongated so that you may align the fan such that it faces the CPU cooler perfectly.
On the floor, you may install two more 120 mm fans. Lian Li ensured that these have access to air by installing feet that lift the chassis off the ground nicely. Unfortunately, as there is no dust filter here, the fans are bound to pull in dust and grime. Considering Lian Li placed such a protective element on the opening in the front, I am surprised this was not considered here. Looking at the ceiling, you can clearly see the two sets of mounting holes for either a 3.5" or 2.5" drive. This brings the total storage capacity to two for the TU150, which is the minimum when considering a system and storage combo.
All the cables within the TU150 are sleeved black and of the default variety, so you won't have any issues connecting them to a modern motherboard. Lian Li has kept the cables nice and short so that you won't have to worry about an excessive cable mess within the system.