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Other => CPU/GPU Bitcoin mining hardware => Topic started by: shmadz on October 18, 2013, 12:23:29 AM



Title: Help! powered USB hub scares me!
Post by: shmadz on October 18, 2013, 12:23:29 AM
I recently bought this (https://www.bitmit.net/en/item/40935-8-port-usb-2-0-panel-hub-with-molex-power-connector) as a hub for 4 little singles and 4 of MrTeal's chili boards.

It has a molex connector and 2 usb connectors that go to the extra usb connections on your motherboard.

When I plug in the molex and plug in the power supply (have not yet hit the power on the motherboard) the CPU fan starts to spin...

Yes, the cpu fan is spinning even when the computer is turned off...


Is this dangerous? Or is this not a big deal and it's just the extra power from the molex feeding back through the USB connectors on the motherboard and all will be fine once there are devices connected on the hub?

Should I try to simply run it without the molex? I'm really not sure that little singles need a powered hub?

I would really appreciate your help. Thank you.


Title: Re: Help! powered USB hub scares me!
Post by: kuusj98 on October 18, 2013, 11:14:36 AM
I am kinda parnanoide on such things, I would not trust it....


Title: Re: Help! powered USB hub scares me!
Post by: fattypig on October 18, 2013, 12:52:33 PM
I recently bought this (https://www.bitmit.net/en/item/40935-8-port-usb-2-0-panel-hub-with-molex-power-connector) as a hub for 4 little singles and 4 of MrTeal's chili boards.

It has a molex connector and 2 usb connectors that go to the extra usb connections on your motherboard.

When I plug in the molex and plug in the power supply (have not yet hit the power on the motherboard) the CPU fan starts to spin...

Yes, the cpu fan is spinning even when the computer is turned off...


Is this dangerous? Or is this not a big deal and it's just the extra power from the molex feeding back through the USB connectors on the motherboard and all will be fine once there are devices connected on the hub?

Should I try to simply run it without the molex? I'm really not sure that little singles need a powered hub?

I would really appreciate your help. Thank you.

That is perfectly normal.


Title: Re: Help! powered USB hub scares me!
Post by: zerocode20 on October 18, 2013, 01:31:18 PM
I recently bought this (https://www.bitmit.net/en/item/40935-8-port-usb-2-0-panel-hub-with-molex-power-connector) as a hub for 4 little singles and 4 of MrTeal's chili boards.

It has a molex connector and 2 usb connectors that go to the extra usb connections on your motherboard.

When I plug in the molex and plug in the power supply (have not yet hit the power on the motherboard) the CPU fan starts to spin...

Yes, the cpu fan is spinning even when the computer is turned off...


Is this dangerous? Or is this not a big deal and it's just the extra power from the molex feeding back through the USB connectors on the motherboard and all will be fine once there are devices connected on the hub?

Should I try to simply run it without the molex? I'm really not sure that little singles need a powered hub?

I would really appreciate your help. Thank you.

Seen this before with cheap powered hubs. Nothing much to really worry about.


Title: Re: Help! powered USB hub scares me!
Post by: Xer0 on October 18, 2013, 05:25:15 PM
Seen this before with cheap powered hubs. Nothing much to really worry about.

that damaged the wifi card in my netbook.


Title: Re: Help! powered USB hub scares me!
Post by: zerocode20 on October 18, 2013, 05:48:25 PM
Seen this before with cheap powered hubs. Nothing much to really worry about.

that damaged the wifi card in my netbook.

I really don't think that is true. The USB 5V power is coming from a voltage regulator on board. Additionally to the voltage regulation circuit, it is protected by a series of diodes and resistors. Also, some manufacturers use phase-change fuses rated at 500mA to prevent this type of occurrence.


Title: Re: Help! powered USB hub scares me!
Post by: leoragraves666 on October 18, 2013, 05:53:39 PM
I would change it for something that doesn't scare me ;D. Seen this before, nothing to worry about


Title: Re: Help! powered USB hub scares me!
Post by: klondike_bar on October 18, 2013, 07:31:45 PM
I recently bought this (https://www.bitmit.net/en/item/40935-8-port-usb-2-0-panel-hub-with-molex-power-connector) as a hub for 4 little singles and 4 of MrTeal's chili boards.

It has a molex connector and 2 usb connectors that go to the extra usb connections on your motherboard.

When I plug in the molex and plug in the power supply (have not yet hit the power on the motherboard) the CPU fan starts to spin...

Yes, the cpu fan is spinning even when the computer is turned off...


Is this dangerous? Or is this not a big deal and it's just the extra power from the molex feeding back through the USB connectors on the motherboard and all will be fine once there are devices connected on the hub?

Should I try to simply run it without the molex? I'm really not sure that little singles need a powered hub?

I would really appreciate your help. Thank you.

as a hub only (BFL stuff grabs power elsewhere) you can skip the molex connector. whats happening is that the 5v feed is being pushed from the hub to your pc's usb ports.

i had a similar powered hub that actually grabbed power from my laptop's usb port and pushed it to the [turned off] psu, causing its fan to spin.


Title: Re: Help! powered USB hub scares me!
Post by: shmadz on October 19, 2013, 12:23:49 AM
Thanks for the replies, I think I will just leave the molex disconnected. I'm pretty sure both the little singles and MrTeal's board are using the USB for data only.



Title: Re: Help! powered USB hub scares me!
Post by: Quix on October 19, 2013, 05:17:38 AM
Proper powered hubs should plug directly in to the wall.