I have 4 USB ports on my 2400+ Athlon computer and they all work. However
only one at a time works. So if I put a scanner and a printer on two of the
USB ports one of them will not work. Does anyone know what might be wrong?
Richard
Check your motherboard- whether the USB ports are powered by
5V or 5VSB. If 5VSB, try rejumpering to 5V (see motherboard
manual).
If you have the documentation for these parts, check what
their rated power consumption is. Also check the USB
entries in (Windows?) Device Manager, as there should be a
report on the current from those devices- which hopefully is
correct, reliable.
The overall trend would be that the multiple devices were
needing more current than they can get, either because of a
power supply 5VSB insufficiency or from each device being
very power hungry in itself. I'd tend to think the former,
that it's a 5VSB power supply problem as the two pairs of
ports on the board should each support 500mA (per 2), so
plugging one device into each port-pair should've worked.
