Let's have a look at one of the many Zacate APU based motherboards currently available.
Alright, the product used here is the Gigabyte E350N-USB3... and yes, that box is as tiny as it looks.
The motherboard is mini-ITX based, that's like 17x17cm. Embedded on the is the AMD E-350 APU and the Hudson IO chipset. Gigabyte added USB 3.0 support for two ports, it also has four USB 2.0 ports, VGA, HDMI and DVI monitor outputs (up-to two monitors can be used simultaneously). Based on a Realtek CODEC we get 8 channel-audio, optionally driven though HDMI, Optical TOSLINK or analog jacks. Next to that a full Gigabit RJ-45 Ethernet jack is there for speedy internet and file-transfers.
With the mainboard flipped around we see the APU (E-350) and IO Hub (Hudson chipset) underneath a small heatsink with tiny yet silent fan. Not all ODMs (Original Device Manufacturer) use an active cooling solution though, MSI for example uses passive design. Gigabyte applied the Ultra Durable design here as you can spot the quality components. We see on 4-pin power header for the APU. Also located here are two DIMM DDR3 slots, we inserted 8GB in total and it ran fine, one downside here, this is a single channel memory controller.
Flipped around we spot a x16 PCIe slot, unfortunately it really only has x4 PCIe lanes available, still it's a nice slot to have on such a small form factor product. Behind it we see no less than four SATA-600 (SATA3 / 6G) ports, nice.