Moving up inside 904, there is allocation for a 90mm rear exhaust fan and an extra cut-out for those wanting to install an AIO CPU cooler – you can feed the cables out and have the radiator fixed to the aluminium grid outside.

Having just a 90mm fan allocation for the rear exhaust alludes to how thin 904 really is and also hints that installing flagship air CPU coolers could be problematic (more on this later).



Over on the other side, the HDD storage cage is actually placed at the very top of the chassis. This cage features three HDD trays which can house both 3.5” and 2.5” drives. IN WIN has given each tray the SATA ports at the back to bring in hot-swappable functionality – there are respective cables for this.

Below our HDD cage are two brackets which can house 2.5” drives. Each bracket can be easily removed by loosening the thumbscrews. From this viewpoint we can also see the 140mm dust filter and bracket for attaching a cooling fan inside 904.