ODROID-U / U2 board is half cased with heatsink. There are three screws to hold the board with heatsink.
There are three nuts mounted on the PCB.
The board is supported by three small nuts to heatsink. Please be careful especially when you connect cables. You must have to hold the board not the heasink when you connect cables. Otherwise, the nuts might be damaged and that could cause the board damage.
Case 1 : USB connector
Case 2 : Ethernet Cable
Case 3 : HDMI Cable and Micro USB Cable
More tips! for cooling fan. The red line is outside.