2 out of 4 usb sockets work

[William Murray <W J Murray rl ac uk>]

  Hello all,
          I am trying to understand a laptop with 4 USB ports,
apparently identical, but all 4 work under windows and only 2 under F8.
If I look in 'hwbrowser' I see 3 controllers, (2 UHCI and 1 EHCI I
think)  but no 'USB UHCI #n' entries like I expect.
  cat /proc/bus/usb/devices shows up 3 controllers, and the USB mouse I
have plugged in.  
  It ALSO shows a device "0baa 0158", which is somehow a Realtek disk (I
don't think there IS one) but not "0bda 8187" (or is it 8189) that I
think the wireless card should be registered as.

   Can anyone suggest how to debug this?
      Thank you,
           Bill
Nb ACPI=off, NOAPIC were needed at boot time...