Why don't front USB ports work with a lot of devices?

J

JoeUser

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I've found using my sig system that things like external 3.5" hard drives (2.5" work fine!) and my Xbox 360 controller won't work or be recognized using my front panel USB ports (USB 3.0 spec) but they work no problem when hooked up to the back ports.

I've ALWAYS had problems with front panel USB compatibility on every PC I've ever built, so I know its not a specific hardware problem with this PC.

Is it the front ports not getting enough power or something? This seems to be a common occurrence among front USB inputs.
 
Holy shit bro, 8 year member with 37 posts?! :eek:

OK, on topic, I don't know how to check front panel power...I'm assuming it works as it can charge devices and power 2.5" external hard drives.

Wiring is fine...if anything it should be better than most considering the length of the cable is much shorter than standard...using a mini-ITX case here.

As far as specifications go the front ports do achieve USB 3.0 speeds, that I know from testing my Vertex 4 SSD on the front ports using an enclosure.

Like I said in my first post, this seems to be an ongoing issue with ALL motherboards and ALL cases I've used over the years...and I've used PLENTY (at least a dozen cases and multiple motherboards). So this doesn't seem to be a problem specific to my current build.

Also, just to be clear, I'm not looking for a fix as I feel none exist...maybe its just the nature of the beast? I mean, if its happened once or twice sure, its a fluke, but for the issue to be normal on every PC I've ever built I feel that theres a bigger wide spread issue here.
 
Some USB 3.0 headers require drivers to work.:D I know my rear 3.0 connections on my Rampage III and IV needed software installed.

I've never had an issue running front USB, but you need to make sure you have the headers connected according to the case manufacturer schematic that came with the case.....altough most are pretty much all the same......

One thing i did notice on my Coolermaster case, where the wiring enters the front connection.....a big piece of plastic.....the wires connect in the same fashion as they do to the motherboard, and over time they worked loose. It was over an hour to disconnect the plastic thing and reconnect the headers....this time I put superglue on the connections so they wouldn't work loose.:eek:
 
Driver are all installed. Cable or connection is not the problem...the connector is properly and securely fastened with plenty of give in the cable.
 
I've noticed my wireless mouse/keyboard has less range on the front panel compared to the back - sounds like a power issue.
 
geraltofrivia said:
I've noticed my wireless mouse/keyboard has less range on the front panel compared to the back - sounds like a power issue.
Click to expand...

That's what I think it is too.

My theory is that the connection between the motherboard header and the actual front panel plug drops the voltage down just to the point of not QUITE being able to power a lot of device. I mean, what other explanation is there really?

However, I'm 100% sure that all motherboard manufacturers are aware of this, so you'd think they could pump a little more voltage to the front panel motherboard headers. This I think might fix the problem but it also doesn't explain why some motherboards I've owned DO pump out more voltage to the front panel ports. A Gigabyte board I had owned used some rapid-charge tech...used more voltage to charge devices quicker, which it did, meaning more power, but still the same issues...so that brings to believe that maybe power isn't the issue after all.

I don't know...like I said, not looking for a solution to the problem, just an understanding as to why this problem even exists in the first place. I know its not just me, every PC has this problem whether you know it or not. You just may or may not have come across a device that displays these issues. That I would consider a fact.
 
I also have had this problem on every PC I've built, I end up just hooking up everything to the motherboard's USB ports if possible unless I'm feeling super lazy.
 
Hi everyone, i have been surprised to find how little information there is out there about usb 3.0 ports , how they are powered, and the typical problems we all run into with them.

I have spent some time digging around the interweb and found a few tid bits of interest, as well as my own experiences:

So to do with the front panel headers on motherboards and adaptor cards for usb 3.0 - the standard output for these connectors is limited to 500 ma , which paired with the front headers themselves being connected with long, high gauge, poorly shielded, and realatively poorly made cables makes a storm of bad communication and under powered front ports, especially when trying to use fast devices like usb sticks and USB 'powered' external hard drives!

I myself have encountered poor write sepeds on my usb sticks in the fornt usb 3.0 ports, and they periodically drop out, as well as serious drop outs or not even being able to read or power external hdd's that are powered through the usb cable. These problems never occur when im using the back ports directly off my mobo or adaptor card, and going back to the power issue, this is because the usb ports on the mobo provide 900 ma + of power, and the front header ports are only given 500 ma of power (found this out through tech support for one of my cases)

Now all this being said, there are other factors at play as well. One big one is poorly shielded internal front panel cables which use high gauge wire and the length of the wire alone creates resistance which slows device communcation down, this problem does not exist on the mobo ports because they are directly connected to the controller with no china made cables in the way to interfere.

Another issue commonly run into is drivers. If you have poor drivers or windows drivers they usually always slow things down or lead to the ports not working at all, so make sure if at all possible that you have the correct drivers for your system.

Lastly i have read of several instances where computer cases have had defective front panel usb 3.0 cables and or ports/connectors leading to a plethera of issues such as drop outs, no communication and poor communication with devices leading to data corruption.

So in conclusion my advice would be to make sure your drivers are up to date and correct, and to really just avoid using the front usb 3.0 ports if at all possible, the rear ones are significantly more reliable and stable

Good day eveyone!
 
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Lydan said:
Hi everyone, i have been surprised to find how little information there is out there about usb 3.0 ports , how they are powered, and the typical problems we all run into with them.
(actual SCIENCE goes here)
Click to expand...

Yeah, hi. Interesting research, a just act of thread necromancy. :D

To add, I'd like to point out an analogy to front panel audio troubles and also to Ethernet wiring rules.

In the case of audio, the front main channel is physically terminated in two opposite points in the system - back IO plate and the front of the case. Correct me if I'm wrong, but this is what I usually see. I'm no doctor, but that's a recipe for a ground loop?
Additionally, the front ports are near vibrating drives, while the rear ones are well fastened. Vibration means microphoning-in a tiny electric current.
Many buzzing/hum problems with audio are solved by muting or outright disconnecting the front panel.

Now, the other thing is related to golden rules of Ethernet. You need the wire pairs twisted all the way, and all it takes is a short distance of untwisted somewhere near the connector or socket to break away from recommended signal specs.
USB is twisted as well to reduce noise and crosstalk.

With USB, though, I have noticed that the passage of time plays a significant role. With a new case and freshly installed components everything seems to work fine - you'd pick any problems up right away as you test a new build. And 5 years later you begin to experience device drop-outs or other stuff. That's my experience anyway.

I guess there are multiple points of failure with front panel USB compared to the rear ports. The signal path is full of gaps in the front.
Mobo pins->panel cable pins->panel cable wire->panel cable pins again->front panel PCB->front panel ports. Compare that with port pins simply going right into the board on the rear.
To expand on your observation about differences in amperage, I'll throw in another theory: simple oxidation? solder point degrading?
 
Power and interference are the two biggest issues I've experienced. For 2.0 it's almost always power. For 3.0 I've had either happen separately or in some situations a bit of both.

Most front panel connections are using sub-par quality cables with wire gauge that's too small to prevent voltage drop and bad shielding.
 
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