Powered hub problem

stevenrw · Nov 23, 2011, 09:51:05

Here's an interesting one...
I have just installed a powered 7 port Trust USB hub and its giving me problems.
Its connected direct to a port off the mobo on the back of the computer, rather than being daisy chained or going in via a PCI usb hub.
If I try booting up without the hub's power supply connected all works fine, but if I try starting the machine with the hub power supply connected, the computer will not start. (W7 Pro 32bit).
The machine goes to start then the steady light goes out on the monitors and all stops. The only way it will start normally is if I either disconnect the hub power supply or switch everything off at the wall, leave it for a minute then try again, at which point it seems to work.
So its obviously a power issue.
Anybody else had similar experiences?

Rik · Nov 23, 2011, 09:54:23

I haven't, but I assume you've only just bought the hub, so I'd suggest taking it right back.

MisterW · Nov 23, 2011, 10:57:13

I had a similar issue with an externallly powered USB drive. IIRC it was an ABIT motherboard and the POST failed if the drive was powered. Can't remember what the error was though and that m/b is no longer in use I'm afraid.

Simon · Nov 23, 2011, 11:24:47

I had the same issue with a powered USB hard drive. If I left it powered on, the computer wouldn't start.

Steve · Nov 23, 2011, 11:52:13

Are these bios crashes or a failure to boot from usb drive with no OS

Simon · Nov 23, 2011, 12:02:17

Me? Dunno, I just leave it turned off.

MisterW · Nov 23, 2011, 12:10:56

QuoteAre these bios crashes or a failure to boot from usb drive with no OS

In my case it stopped the Bios POST sequence and beeped. IIRC the m/b had a display giving the error number but its a long time ago. I've got a feeling that it was reporting an error on the 5v Standby line...

Technical Ben · Nov 23, 2011, 16:03:18

~~Sounds like some sort of power routing problem. IE the powered USB hub is trying to power the PC, and that's not good (power is not suppose to go back that way! ).~~
(A little Googling suggests it's most probably a hardware conflict)

If it's just a plain old hardware conflict, it's still best to send it back. As hopefully a different model will work fine.

Ray · Nov 23, 2011, 16:06:58

I suspect it's faulty, they should work OK, I've been using 2 Belkin 7 port powered USB hubs for 3 or 4 years now without any problems.

Glenn · Nov 23, 2011, 16:28:26

Is the BIOS set to boot first from USB? With no power to the hub it may not be seen by the BIOS.

zappaDPJ · Nov 23, 2011, 16:34:32

It could be faulty, I certainly wouldn't rule that out but it could also be a BIOS issue. If the BIOS is old is might not be configured to cope with the device or it might be treating it as a bootable device. I'd at least check your BIOS settings to see if it's trying to boot from it at power up.

I'd take a guess that if you add power to the device after the POST everything will work but that's not something I'd recommend.

[EDIT] Or what Glenn said

Must type faster...!

Steve · Nov 23, 2011, 16:43:56

If you google 'PC fails to boot with USB powered hub' you'll find your not alone by any means,some combinations of hub and MB work others don't.

ie http://www.tomshardware.co.uk/forum/268814-12-ep45-ud3r-acpowered-connected-start

stevenrw · Nov 23, 2011, 17:01:24

OK guys, thanks for your help, its much appreciated as always. It may well be a support issue with the mobo although the Biostar P43-a7 isn't exactly an old board. I have an old pci usb expansion card - I'll pop that in and send the hub back/give it away/consign to landfill. I'm all for an easy life these days...Ah well, it was worth a try.

Rik · Nov 23, 2011, 17:07:17

Aren't we all.