Front USB Ports not working properly

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guy3g

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I have a HAF 912 case and the front USB ports work for most devices, once I try to use a big portable drive or a USB Modem it just wont work. Is there a problem with the amount of power coming thru. If it is how do I solve it.


I have updated to the newest motherboard drivers still not luck, the back usb ports on the motherboard work perfectly.
 
I'm sure I read somewhere that there was an issue with a few hafs and their front usb ports failing.. google it
 
Yes, it's almost certainly power. What you can do is use a double USB connector to one.
Check which header the ports are connected to as well. Can you try USB3?
 
guy3g said:
I have a HAF 912 case and the front USB ports work for most devices, once I try to use a big portable drive or a USB Modem it just wont work. Is there a problem with the amount of power coming thru. If it is how do I solve it.

I have updated to the newest motherboard drivers still not luck, the back usb ports on the motherboard work perfectly.
Click to expand...
Like they're saying: this is a power issue, not a driver one. But, to answer about how to solve: what >I< would do (but haven't yet (I just haven't had something that draws enough from a desktop case's front USB)) is cut the RED wire (+5Vdc), probably put an extension on it (which means getting more red wire (say from a dead power supply)) and jacking into the case's many-hundred-watt power supply for NO shortage ever again on that port.

But that's me. :D

Nota bene: I ran a few (ok, a good few) searches to see how others have done this before and, well, there's REALLY little info out there on this subject so, should you choose to proceed: you're on your own, sport ;); it's not my fault if you blow something and ... YMMV. :erm:

But I'm keen to at least try it as-is although stepping the 12V line down to 5V through a regulator is probably the better bet. :p
 
Use a USB Y-cable to take power from both ports, as is required by most all 2.5" HDD's, irrespective of front or back ports.
 
bdt said:
Like they're saying: this is a power issue, not a driver one. But, to answer about how to solve: what >I< would do (but haven't yet (I just haven't had something that draws enough from a desktop case's front USB)) is cut the RED wire (+5Vdc), probably put an extension on it (which means getting more red wire (say from a dead power supply)) and jacking into the case's many-hundred-watt power supply for NO shortage ever again on that port.
Click to expand...

While that would work the USB standard is a maximum of 900mA(I think), so if you have a faulty device it's not going to be pretty. Since the return path is through the motherboard think what a short would do to to it:)
 
KhoisanX said:
While that would work the USB standard is a maximum of 900mA(I think), so if you have a faulty device it's not going to be pretty. Since the return path is through the motherboard think what a short would do to to it:)
Click to expand...
Actually, it's 500mA/port, and you're right: that opener really is decidedly cowboyish. ;) Better would be to make up a wee circuit such that you feed the case USB cables to 4-way headers on THAT board with 2-way cables (the data lines only) going out from there to the motherboard.

The magic in the middle (I'm sure you've got it, I'm expounding for the non-elec fellas) is a 7805 regulator that you feed from the PSU. Should you (highly improbably but, you know) get current runaway on that the 7805 will go into thermal shutdown long before the PC PSU is likely to even feel it. And none of it goes near the board.

Do it right/nicely/prettily/properly :rolleyes: and you WILL end up spending (so much) more on the ancillary bits - the solder-pad board, headers, connectors, etcetera - than the actual regulator.
 
Some mobos have use a common power line for all or most of the USB ports, so pulling current on any others can affect your 'open' port. Quick and easy solution is to get a powered USB hub (ie one that has its own power supply).
 
Arthur said:
Some mobos have use a common power line for all or most of the USB ports, so pulling current on any others can affect your 'open' port. Quick and easy solution is to get a powered USB hub (ie one that has its own power supply).
Click to expand...


didn't know you get a powered usb hub will anything work with it
 
guy3g said:
didn't know you get a powered usb hub will anything work with it
Click to expand...
You get all sorts and totally; of course with the caveats that you now have another brick in the plug-cluster at the wall whose cable needs to be long enough for you ..and, life being what it is, they like to not be. :rolleyes:
 
Generally, front USB ports are a bit low on power ( due to the motherboard, not the chassis ) - All my old Asus boards had the same issue.

Since I moved to my new Gigabyte one, ( P55-UD5) my front usb normally seems to be able to power my external drives ( though some of the older ones still need to be powered by the back ports :( )

Basically, it's a limitation of the USB output port on the motherboard most likely, the only thing that changed that made mine work is the motherboard itself.
 
bullzeye.za said:
Generally, front USB ports are a bit low on power ( due to the motherboard, not the chassis ) - All my old Asus boards had the same issue.

Since I moved to my new Gigabyte one, ( P55-UD5) my front usb normally seems to be able to power my external drives ( though some of the older ones still need to be powered by the back ports :( )

Basically, it's a limitation of the USB output port on the motherboard most likely, the only thing that changed that made mine work is the motherboard itself.
Click to expand...

Re-reading that, I'm not sure if I made sense..
 
If the motherboard can supply less power to the front ports that the rear then it's a crap motherboard which does not conform to the USB specification. There is no differentiation in the spec for "front" and "rear" ports, a USB compliant port is a USB compliant port.

Yes, the cable that attaches the USB header on the board to the USB connector on the chassis does add a small series impedance to the power supply for the port, however it should negligible.

If your external 2.5" external drive was supplied with a Y cable and you are connecting it with a single cable to front OR rear ports then it is your fault is does not work as it says on the box, as many external 2.5" HDD's plus the associated internal electronics draw more power than the specification allows for.

Some drives draw less which may allow you to get away with it, but if it's supplied with a Y, use it!

And if it's an el-cheapo and the manufacturer is trying to cut corners, it may only be supplied with a single when in fact it needs a Y.
 
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