Beagle board Fail booting

I've a BeagleBoard xM rev C, i'm using an 5V-2A power adaptor.

Everytime i try to boot the beagle with two usb plugged it restarts
itself, if i just plug one it boots correctly, i was using a 1A power
adaptor, but someone told me it was to low in A, so i change it but
the problem is there anyway, if i use 2 usb ports it fails booting
after loading the kernel, any help is appreciated.

What do you have plugged into the two USB ports?



  Please use 5V 3A power adapter.