VIA Technologies VX800 Technical Manual page 13

(3) JP3: USB Power On Function Setting (3-pin)
(4) JP4: LVDS 5V/3.3V Function setting (3-pin)
1
1-2 closed
JP3
3
1
JP3
2-3 closed USB Power On Enabled
3
1
JP4
3
1-2 closed: PVDD= 5V
8
USB Power On Disabled
JP4
1
3
2-3 closed : PVDD= 3.3V