Inside the Antec One
Both panels are attached to the chassis using thumbscrews. The motherboard tray has a huge hole for you to access the backplate of the CPU coolers without having to remove the motherboard from the case, several holes for you to route cables behind it, and several clips for you to fasten cables using cable ties.
In Figure 12, we get another overall look inside the case. Expansion cards are fastened using regular screws. The Antec One supports video cards up to 10.5” (266 mm) long and CPU coolers up to 6.1” (155 mm) tall.
The power supply is installed at the bottom of the case, and it can only be installed with its bottom fan facing down. As already discussed, the case comes with an air filter for the power supply fan.
There is space for installing an optional 120 mm or 140 mm fan on the bottom panel. If a 140 mm fan is installed, you can only install power supplies that are up to 5.5” (140 mm) deep. With a 120 mm fan installed, you are able to install a power supply up to 6.3” (160 mm) deep. If you have a power supply deeper than that, you won’t be able to install a fan on the bottom panel.