Re: Dell Monitor USB ports don't recognize some devices

Tech-Archive recommends: Repair Windows Errors & Optimize Windows Performance

"Lee M." <lmacmil@xxxxxxxxxxxxx> wrote in message news:opGdnWlWULzKW9_VnZ2dnUVZ_sDinZ2d@xxxxxxxxxxxxxx

"Shenan Stanley" <newshelper@xxxxxxxxx> wrote in message news:ugux5j$wIHA.3780@xxxxxxxxxxxxxxxxxxxxxxx
Lee M. wrote:
I have a Dell LCD monitor with 4 auxiliary USB ports. I have my
keyboard and a Sandisk card reader attached and both work fine as
does my Garmin GPS when I need to upload a new map. When I plug in
a Sandisk MP3 player or my Kodak digital photo frame, neither one
shows up in Explorer. Both are recognized by my Vista laptop. The mobo USB ports recognize everything that is plugged into them. Does this sound like an XP problem (I am running XP Home SP2) or a
hardware issue?

If the devices *are* recognized in the USB ports that are on the motherboard... just not when plugged into the monitor ones - I think the answer is obvious.

(Hardware)

However - it would not be the first time I have seen it where people get som many USB devices they atart using a 'hub' device and that hub device cannot handle everything connected to it because of power reasons.

--
Shenan Stanley
MS-MVP
--

Is it possible to determine the max power a hub device can provide? Or to rank USB devices in order of power consumption?

Yes, by examining the specs for the devices. But if the ports are damaged in any way, the specs don't mean much.

USB ports provide a maximum of around 500mA. If the hub is passive, that is split between all of the ports, including the one the hub is plugged in to.

Powered hubs can provide more power, but not more than the power source can provide.

HTH
-pk

That way I could put the heavier users directly into the mobo ports and use the hub ports for the low power devices.

.

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