Re: Power Tolerance

Piggy <piggy@xxxxxxx> wrote:

Anyone know what tolerances should be expected from a PC's power supply? ie
12v +/- ? 5v +/-? etc

5%

I have a problem with external USB hard drive devices loosing
connection, After some time checking drivers, power settings BIOS etc
etc the only 2 things I can see is 1 the main board is defective or a
problem with the power supply??

Any ideas?

Do the USB devices have their own power or do they get it from the USB port ?

If they get it from the USB port, some ports can be inadequate, cant
provide the full legal power. In that case a powered hub can fix that.

If they have their own power, it can be a flakey
USB port, try a different one if you can.


.

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