The M3A790GXH/128M in a Full Size ATX board. It has 2 PCI, 3 PCIe slots encoded in three different colours. (green @ x16 mode, blue @ x8 mode, orange @ x4 mode). There is another PCIe x1 next to the north bridge which is covered by the heatsink. Next to it is the sideport memory. A peddle card is required to switch the board's operation when in CrossFire mode.  To the rear corner, we can see the audio codec from Realtek, GbE controller chipset.  To the right corner of this mainboard, we can find the eSATA connecting port. 8 pin AUX power supply connector. The board is using a 5 phase power regulator circuit.

On the right bottom of the board are 4 DIMM slots supporting up to 4 x DDR2-1600 (max 16GB in total). Below it is the 24 pin connector, a IDE slot. The south bridge is on it's left and there are 6 SATA II ports. To the left is the orange coloured front panel connector and the blue coloured USB bracket connectors