I tried the onboard USB, the two rear connector and the front, and they work without problem.
I mounted a pci USB card, a D-Link 4+1 ports, and it goes very well!
So with 7 USB port (I'm thinking about to connect the second port in the front panel...)
I cannot complain myself: all is working here, even when I connet external HD, camera, printer, mouse, joypad and stick.
Poseidon recognise all of them.
Fortunately, nothing exploded......

P.S: Welcome back Pahantom! I noticed you change your signature...
Really happy!