Noob question on USB connections

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Durandal

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Hi, have been following the many conversations on the Cell C modems in another forum, and one guy was claiming that he had much better speeds when he moved the modem from the USB ports on the front of the desktop, to the rear. One or two replies mentioned different USB port qualities/versions as being a possible reason for this. Are the USB ports on a desktop PC allocated different speeds?! Could anyone advise on what these guys are talking about and if this is an issue, how I would work out the best ports to use?:confused:
 
Generally the back usb pots are stronger.

They(back ports) are directly attached to the board where the front ones are part of the PC chassis & connect to board via cable(s).
 
Durandal said:
Hi, have been following the many conversations on the Cell C modems in another forum, and one guy was claiming that he had much better speeds when he moved the modem from the USB ports on the front of the desktop, to the rear. One or two replies mentioned different USB port qualities/versions as being a possible reason for this. Are the USB ports on a desktop PC allocated different speeds?! Could anyone advise on what these guys are talking about and if this is an issue, how I would work out the best ports to use?:confused:
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The back ones are connected closer to the power so are generally usb 2.0, the front ones just go into the motherboard via a cable and are not powered like the back ones so are often only usb1.0. Though this is not always the case, but pretty common. Normally the only speed issues you would get would be with external drives and such.
 
invader said:
Yea, the back usb Ports have more voltage out put than the front usb
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I lol'd.

@OP, the difference is only in 2 things, signal reception (that's from moving the modem) and USB version. Front ports are usually USB 1.1 (or maybe even 1.0) and the back ports might be 2.0. This is because the cable to connect the device to the mother-board in a front port configuration is relatively long, meaning it becomes inductive at the high frequencies USB operates. The rate is therefore decreased to have a relatively error-free signal.
 
Um... no... on really old motherboards this is perhaps the case where front ports are sometimes USB 1. But any modern motherboard the back ports are exactly the same as the front. Voltage drop? Please!! The drop will like 0.01V, which wont affect anything.
 
Archer said:
Um... no... on really old motherboards this is perhaps the case where front ports are sometimes USB 1. But any modern motherboard the back ports are exactly the same as the front. Voltage drop? Please!! The drop will like 0.01V, which wont affect anything.
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Well I have a dual core thats like this. Wont say its new, its around a year old, but its not old. Got the same issue with my wifes laptop, ports on the one side work and ports on the other side dont have the juice the ones close to the power supply have.
 
w1z4rd said:
Well I have a dual core thats like this. Wont say its new, its around a year old, but its not old. Got the same issue with my wifes laptop, ports on the one side work and ports on the other side dont have the juice the ones close to the power supply have.
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Laptops often only have a couple powered ports. Has nothing to do with voltage drops. If the voltage was wrong then nothing would ever work in that port.
 
Archer said:
Laptops often only have a couple powered ports. Has nothing to do with voltage drops. If the voltage was wrong then nothing would ever work in that port.
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Okay, but my pc is a pc. The duel-core one.
 
Archer said:
LGA775 by any chance? Model number? Still has nothing to do with voltage though
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Ill check when I get home. Its my gaming PC and at home. Work with a laptop at work. I come across this problem on a regular basis so my machine is certainly not unique, but let me get the model when I get home.
 
WHAT!?! USB 1.1 ports on the front. I call BS! Must be on really old motherboards.
I've not seen a motherboard with both types of USB ports listed in the last few years. And I look at a lot of motherboard specs.

I agree with the 'signal strength' assertion. (position of modem)
Also it is possible that the lower quality connection the front ports have to the motherboard (those medusa's hair wires that come off the internal USB connectors picking up noise), (compared to the ones directly on the board at the back), suffer from more dropped packets (after failing the USB CRC-16 checks).
Maybe that person just had really k@k connecting wires to the front of his case. I've never noticed any difference, and I've done plenty of flash drive/hard drive speed tests.

I'm really surprised at how many people jumped on this bandwagon that the front ports are USB1. Nonsense.
 
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Funny thread of the day. :D

It's more like a GSM reception/interference thing.

USB2.0 = USB2.0, that's why it's a standard.

It could also be an enumeration/driver thing, device requests "high power" mode from host.
 
kayvee said:
It could also be an enumeration/driver thing, device requests "high power" mode from host.
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That wouldn't explain why its different from the front to the back.
-
Maybe its the person's perception. Maybe it was network congestion, signal strength, etc. How do we know this hearsay test was conducted scientifically?
 
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Lope said:
WHAT!?! USB 1.1 ports on the front. I call BS! Must be on really old motherboards.
I've not seen a motherboard with both types of USB ports listed in the last few years. And I look at a lot of motherboard specs.

I agree with the 'signal strength' assertion. (position of modem)
Also it is possible that the lower quality connection the front ports have to the motherboard (those medusa's hair wires that come off the internal USB connectors picking up noise), (compared to the ones directly on the board at the back), suffer from more dropped packets (after failing the USB CRC-16 checks).
Maybe that person just had really k@k connecting wires to the front of his case. I've never noticed any difference, and I've done plenty of flash drive/hard drive speed tests.

I'm really surprised at how many people jumped on this bandwagon that the front ports are USB1. Nonsense.
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Overreact much?
 
Lope said:
That wouldn't explain why its different from the front to the back.
Maybe its the person's perception. Maybe it was network congestion, signal strength, etc. How do we know this hearsay test was conducted scientifically?
Click to expand...

The first point I offered could. Unscreened/poor screened cable between board and front panel USB connector, position of modem relative to case, etc.

Some mobos also have multiple USB controllers for the various ports, so drivers still could be an issue, although admittedly less likely.

Edit:

Anyway, could be a number of reasons, some light reading for you.

http://www.beyondlogic.org/usbnutshell/usb2.shtml

See sections "Speed Identification" and "Power".
 
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kayvee said:
Some mobos also have multiple USB controllers for the various ports, so drivers still could be an issue
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Ah, I see. Interesting point.

w1z4rd said:
Overreact much?
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I find it wrong how everyone just agreed with BS, dispensing wrong information just because a bunch of other people said it. They clearly don't know what they're talking about, but they make it seem like its true because so many said the same thing.
I'm against deception and misinformation. I think my reaction was necessary to counteract the strong support for the "usb 1.1 theory". You can think what you like.
 
Oh, nevermind, it was invader that said the retarded voltage thing. He is a bit of a nutter judging by his recent posts in off topic
 
Lope said:
I find it wrong how everyone just agreed with BS, dispensing wrong information just because a bunch of other people said it. They clearly don't know what they're talking about, but they make it seem like its true because so many said the same thing.
I'm against deception and misinformation. I think my reaction was necessary to counteract the strong support for the "usb 1.1 theory". You can think what you like.
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Could you tell me why my front ports only copy at around 600KBs and my back ports copy at around 20MBs?

Could you tell me why large external works on the back port, but not on the front port? Though the small external works on both ports but at a limited speed on the front port?
 
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