Friend wants to know if a relatively new low-end Toshiba laptop can run his 22" monitor via VGA port without burning out the PSU or GPU chip?
What he already knows is that it won't tolerate a USB hub (or at least the one he was trying) so assumes it might be low powered.
It's new and under warranty for another year so not too worried about it but I told him I'd ask our hardware experts.Thanks.
The 22' monitor has it 's own power supply. I am pretty sure the VGA video port signal would not put much power demand on the laptop.
That's what I thought, Doc, but he was concerned that when he tried using a USB hub for more than 3 USB devices (mouse, keyboard, printer, speakers) it seemed to overpower the USB controller.
I noticed the hub he was using has a power port on it so wonder if it shouldn't have its own power, too. That said on my old HP 510 with 2 USB ports it can run 5 devices plugged into a hub with no external power without hesitation.
Yes, they should probably use a powered USB hub. Their ports may even be USB 1.0 if it is an older laptop.
It's actually new, but not USB 3.0 and pretty low end Toshiba.
Thanks Doc. Nice to know you can still work in sub-Jiggawatts.
The spec for a normal (not low power) USB port is a max current draw of 500 ma per port. The port will automatically shut down if you exceed 500 ma. An unpowered USB hub will draw all its power from the one USB port its plugged into. If the combined current draw of the devices plugged into the unpowered USB hub exceeds 500ma the host port will shut down. If you use a powered USB hub it gets all its power from the power adapter and you won't have to worry about overloading the host USB port. If it's a 4 port hub the power adapter will (usually) be rated for 2 amps.
As far as I know there is no power supplied to speak of over the VGA port. It's just the VGA signaling. I wouldn't expect the monitor to draw any appreciable amount of power from the VGA port.
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