Help : USB Hub Problem .,

[majithia23]

Allright guys ,

i bought a USB hub to extend the USB ports of my laptop available for use at one time .

Its a 4 port USB hub and is of good make , not the cheap chinese ones .

so the thing is if i attach 2 or more than 2 pen drives , i can access them and read their contents .

but the moment i try to write anything , that is Copy/Paste or Cut/Paste , either between the drives on the Hub or between the Computers HDD and the drives on the hub ,

i get an error --- The Drive is not Accessible !

the write process starts , but suddenly stops with the error stating the Location is no longer accessible .

its like the whole hub goes dead , and so do the attached drives .

after cancelling the process , the hub is again recognized by the laptop and then comes the message -- Scan drives for errors !

meaning - - what i feel is that during write process the Hub goes dead , !!

so is it normal to happen like this ?

or is this a hardware error in the Hub ?

or a Hardware error in the Laptop ?

i paid more for this hub , simply because of this same reason , that the cheap hubs dont allow all the hubs in them to be used at the same time and that they go dead .

but seems to be happening with this too .

( either its normal , or i got ripped by the electronic store guy and then i need to get hold of him and get a replacement )

so what say . . . . .

[ck_kent]

I've had a similar experience, but not with a USB hub. Mine was with an external 2.5" HDD. I got exactly the same problem before when copying files to it. When I connect the drive, it will get recognized. When I start copying to it, the "Drive is not accessible" error appears and like you said, after cancelling, the drive gets recognized again. What I did was changed the USB cable and that solved my problem.

So, how is your hub connected? Is the cable removable?

[speedy57]

When you attach 1 or 2 pens, is it happen too ?

Max. current 2A @ 5V

[rudrax]

I got a chinese one and experienced similar problems that you are having now..You know what I did at last?

HAMMERED THE SHIT :angry:

[majithia23]

I've had a similar experience, but not with a USB hub. Mine was with an external 2.5" HDD. I got exactly the same problem before when copying files to it. When I connect the drive, it will get recognized. When I start copying to it, the "Drive is not accessible" error appears and like you said, after cancelling, the drive gets recognized again. What I did was changed the USB cable and that solved my problem. So, how is your hub connected? Is the cable removable?

exactly . this is the same error .

the hub has a long cable and a USB port at the other end , which obviously plugs into the laptop .

but i dont think the cable is removable .

its one complete unit .

i attach my external HDD , wireless Keyboard Mouse , and Pendrives to the hub .

its the write process that doesnt seem to go well with the Hub .

so what i understand ,

there could a problem with the cable in this Hub ?

When you attach 1 or 2 pens, is it happen too ? Max. current 2A @ 5V

i attach my external HDD , keyboard mouse , pen drives to the hub .

and they seem to work .

its only when i start copy paste or cut paste , between either the external or internal storages or in between ,

when the hub goes dead .

so this current rating you mention is constant or does it keep varying according to demand of the attached hardware ?

shouldnt the USB amplify the current so that the ports keep functioning and dont fail . ?

[speedy57]

It's the max. current that your USB Port can deliver so when, for example, your external HDD is just plug in it's not the same current as the HDD is writing or reading. Check what's the current that your HDD need.

Technically, you can connect up to 127 individual USB peripherals at one time. Due to the fact that some devices reserve USB bandwidth, the practical maximum of devices is less than the theoretical maximum.

[ck_kent]

I've had a similar experience, but not with a USB hub. Mine was with an external 2.5" HDD. I got exactly the same problem before when copying files to it. When I connect the drive, it will get recognized. When I start copying to it, the "Drive is not accessible" error appears and like you said, after cancelling, the drive gets recognized again. What I did was changed the USB cable and that solved my problem. So, how is your hub connected? Is the cable removable?

exactly . this is the same error .

the hub has a long cable and a USB port at the other end , which obviously plugs into the laptop .

but i dont think the cable is removable .

its one complete unit .

i attach my external HDD , wireless Keyboard Mouse , and Pendrives to the hub .

its the write process that doesnt seem to go well with the Hub .

so what i understand ,

there could a problem with the cable in this Hub ?

Well, based from my experience, yes the problem is with the cable. The problem is, yours is not removable. :(

Have you tried connecting it to another USB port in your laptop? Or, try using it on another laptop/desktop and see if the problem replicates.

[majithia23]

It's the max. current that your USB Port can deliver so when, for example, your external HDD is just plug in it's not the same current as the HDD is writing or reading. Check what's the current that your HDD need.

Technically, you can connect up to 127 individual USB peripherals at one time. Due to the fact that some devices reserve USB bandwidth, the practical maximum of devices is less than the theoretical maximum.

the hdd is a standard 5400 rpm WD drive . dont know how much current it uses .

but if i understand correctly what you mean to say , then ports is not a n over kill and all the hardwares attached to the hub should work ?

right ?

or something else ?

Well, based from my experience, yes the problem is with the cable. The problem is, yours is not removable. :(

Have you tried connecting it to another USB port in your laptop? Or, try using it on another laptop/desktop and see if the problem replicates.

yes i did attach it to a different port also . but the same error .

right now i dont have access to a second computer . will head to over my friend in the evening .

but still , its not clear , whether this is normal or some kind of an error .

anyone who uses a multi port USB hub might be better able to address the concern .

[speedy57]

It's like you say, technically, you can connect up to 127 peripherals, but when you connect just 1 peripheral (without extenal power) that need 2A then it's 0veR :P

[ApollonStar]

Hi everybody,

first of all I`m new to this forum and please excuse my bad english, i hope everybody understands me!

Speedy57 has got the point and is almost right. So her comes the solution.

I asume as I´ve read the replys that your hub does not have an external power source, also your 2,5" Harddrive, correct???

The USB specification requires a MAX. Output per USB controler as speedy 57 says, so if the external devices you use have not a power suply they arent funktioning as a HUB, but as an extension, lengthening. The MAX Cable length is specified as 1.5 Meters to your device to function properly. This is the whole length every thing connected from the USB plug from your PC or Laptop.

So if you use an USB Hub with external Power and you have trouble than you can check the quality of your cable (It should be high quality shield) and the compatibilitie of the Controler and Hub Chips from the PC and your device.

If thats not the case and you do not have an external power to the HUB, do as follows:

-- Check the specifications of the Hub and your PC (Cablelength,....)

-- Boot into your Windows, do not have pluged in any USB device!!!!!!!!!!!!!!!!!!!!

-- Check your Motherboard or your Manufacturs Manual in how much USB Ports he devided the USB Controler or Controlers (New motherboards have up to more then 12 USB Ports) and which numbers (Position) is the First USB Port at the first USB Controler at your PC.

-- PlugIn your HUB at that first USB Port. Wait for Windows recognition. Reboot

-- Open "My Computer", right click on one Partition (does not matter which), select properties, goto Hardware, select your USB Hub (Maybe Manufactors Name), select properties, goto the second tab (dont know hows the name in english) and ifs not alredy, chose the second Button from above "Optimize for speed", make sure to uncheck the "Device Cache" ifs enabled but do activate the button "Windows Cache" if windows gives you the choise!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

-- Confirm everything with "OK" and make a reboot.

-- If booted into windows, not before, connect your Device to the Hub, one and only one, as it functions now as an extender and gives the power of your PC.

-- Follow same steps as above to activate the "Optimize for Speed" for the device you pluged in. Exactly the same steps. Make reboot. The device must be pluged in as the reboot happend. Done!

If your encounter problems during reboot or your pc hangs, than you have compatabilities problems. Throw away your USB HUB!!!

In no circumstanses this methos is for 2,5" Drives, they always need external power supply. The two USB Cable solution is not an solution, its Manufators Crap.

Maybe its funktion, but I guarantee you, that one Day you will end with lost Data, not readeble Harddrive at all with corrupt file system loosing all your Data and in the worst case of exceeding Max Power Output, your PC ends in the recycler, as you burnd your Motherboard!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I will not write her an complete article including all details, that would be to much, but to everybody:

-- Do not buy USB HUB without external power supply. Its crap.

-- Do not plugin 2,5" Drive with two cable solution. Its crap.

-- Buy case with external power supply. Buy external case with power suplly and Hard Drive individually. Put them together, this is the best solution.

-- Check the Manufators Compatibilities with the USB Chips. Write them if no information is available. If he does not reply, doent buy from them.

-- Follow with all devices steps above. And you will never have a Problem.

Good Luck

[majithia23]

wow ApollonStar !

that is one hell of an explanation to a problem . dont worry , your English is perfect ! appreciate it ...

i get everything you mean to say ! ;)

and thanks to your reply , i just checked the USB hub to see for provision of any external power source and YES it does have.

there is a small hole at the back of it to attach a power adapter .

checked the manufacturer's website , it also reckons the provision of attaching external power source . :)

the company even provides a power adapter with one of its other higher models

( dint realize it before as to what this small hole meant . )

so basically , we definitely need an external power source with a hub so as to allow all the attached hardwares to function properly .!

the adapter provided with the other higher end model is rated at 2.5 Amp .

so that should be sufficient for this hub also ? or does it require some else rated adapter ?

i will connect it in the morning ....

[ApollonStar]

wow ApollonStar !

that is one hell of an explanation to a problem . dont worry , your English is perfect ! appreciate it ...

i get everything you mean to say ! ;)

and thanks to your reply , i just checked the USB hub to see for provision of any external power source and YES it does have.

there is a small hole at the back of it to attach a power adapter .

checked the manufacturer's website , it also reckons the provision of attaching external power source . :)

the company even provides a power adapter with one of its other higher models

( dint realize it before as to what this small hole meant . )

so basically , we definitely need an external power source with a hub so as to allow all the attached hardwares to function properly .!

the adapter provided with the other higher end model is rated at 2.5 Amp .

so that should be sufficient for this hub also ? or does it require some else rated adapter ?

i will connect it in the morning ....

This was actally my first Post at all in a Forum, and yes i begun with nsane. And im so happy you got the point.

You are right. Technicaly an USB HUB without an external power source cant be an USB HUB, but as i said, only a extension lengthening to your Pcs USB Ports and in reality not even for all USB Ports, but for only one USB Port from your Pc. To avoid compatabilty issues you have to choose the first USB Port on your First USB controler. The whole thing is a Joke and must be forbidden by LAW!!!!!!!!

Now, as i read your reply you made your Job and got it.

On your USB HUB device, maybe printed or else it must (IT IS A MUST FOR ELECTRONIK DEVICES) say the Volt and Ampere and other Specs for that device. You do not need to Buy from the same manufacture (Maybe it is a garantee issue if not, but thats not our problem here and another article), you can buy anything that meet the same or the minimum Specifications of the Power Source and minimum and maximum Inputs of the USB HUB.

I think that to almost 100% even the higher devices as you wrote will have the same adapters. Its a costy thing to make extra power sources for every device in the same group. On the Manufactors site, normaly, at the infos of your USB HUB, it has to say the optional power source to buy from them, and i assume that it will the same as the other devices you said. But thats not a garantee. They all want to make money, they sell the low end as you bought (As for me this should be forbidden as ilegaly), they sell the high end with power source and maybe this is the best-value here. Personaly i prefer USB HUBS that have an IN build power source, next thing is the Hub must have more than one USB controler and an up to date and high-end USB Bridge chip, so you can make WITHOUT ANY BANDWIDTH PROBLEMS, more than one connection to your HUB.

I mean as an example, you Print with your USB Printer, READ from your USB STICK and write on your USB Harddrive connected to the USB HUB the same time DATA that you read from the USB STICK and DATA that you READ from four Pc. And if thats function at the highest Speed of the specifications an you do not have any other problems, than youve done a good job and bought the right things.

One thing last, USB HUB EXTERNAL POWER SOURCE, DOES NOT REPLACE AND SUBSTITUES EXTERNAL POWER SOURCE OF ANY, ANY 2,5" Harddrive Case. They always need their own power source.

Excuse me, one more: If and only if, in the property windows of your Hardware device, as i wrote above, of the WinOs you use, does not have the "Optimize for Speed" entry or in the "Format Dialog" for your Harddrive it does not show the NTFS menu to format, you have to first delete your partitions (not your windows, on the new external stick or harddrive), for new devices as combos of separately case and drive or new sticks follow steps above and plug the case first and then case with drive in it, as i wrote above. Then activate the Optimized for speed, make reboot, check again if its correct in windows and now you have the NTFS Format option in the format menu and vice versa.

Hope now you have all the Input you need, no more questions and a successfull outcome!!!

Good Luck.

[majithia23]

great !

you ApollonStar are one Smart Ass ! ;)

very knowledgeable post ! and a perfect start in the Tech nSane community !

Keep it flowing !

coming to the issue ,

i just checked the Hub and the Website , but there are no mentions as to what specs pertain to the external power port on this model of Hub .

on the second model , supports 10 USB ports , this is what it says - :2.5AMP Adapter included to use all 10 Ports "

so what say ?

i have a few spare chargers and adapters at home with varied ratings ,

so i can hook up some with this .

i do understand what you mean to say by using multiple hardwares simultaneously from a Hub and the importance of proper power source to run them .

and could you please be little more elaborate where you mention -- Optimize for speed .

coz i couldnt see this option anywhere .

[ApollonStar]

Thanks!

Normaly "ON" the device USB HUB you have, printed above them, it must say the specs. If it does not, i would recomend, before you make any experiments with inpropper power settings with all the chargers you have, to write email to the support page of the manufacture and wait for the reply.

The thing with the "Optimized for Speed" or something similar alike, i cant go much into it, as my knoleegde of the language on your OS is not enugh, also as i said my english is not very good.

My OS is winXP. For you to see what i mean do as follows exactly. Assuming you have at least USB2 USB Ports at your PC and an USB2 Stick.

-- PlugIn your USB Stick in one USB Port directly in your PC. Nothing else should be plugged in, at any USB Port, nothing!!!

-- Then do as i already wrote: "Open "My Computer", right click on one Partition (does not matter which), select properties, goto Hardware, select your USB Stick (Maybe Manufactors Name), select properties tab, or DubbleClick in the windows you are and see the USB stick device or the manufactors name. Same thing happens, it will open the devices Propperties. Then in the new window (Properties window) goto the second tab (dont know hows the name in english) and ifs not alredy, chose the second Button from above "Optimize for speed", make sure to uncheck the "Use Device Cache" ifs enabled but do activate the button "Use Windows Cache" if windows gives you the choise!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! This last choise depents on the Hardware and the USB Controler thats built in the device. Sometimes you see it in the property dialog (Maybe grayd out), sometimes not and sometimes you have the choise. If its there, enable only the windows cache, if its not its also OK. But in no circumstances the Button to use the devices cache.

The reason to not use the devices cache is, imagine have a file to execute from the stick, then windows would use the stick as a cache and not the disc where your operating system is. Please i cant go in details, this would make a book out of this post.

This is the method for all USB devices plugged in for the first time to give you MAX. Speed and in the situation off a Harddrive or a Stick, specificaly in XP, its the only method to have in the Format menu the Format as NTFS option. If you do not activate the Speed option you can only format as FAT. I know that Vista and Win7 make this a little differently, as in most situations the Optimized button is enabled default, but not always!!!!!! And rememeber the new options you make require always a reboot, and also in Win 7 even if after you pluggin the USB device first time in the Properties dialog says that its already optimized for speed or after you enable it no reboot order comes from windows!!!

I hope you can follow the steps.

Maybe some other Member knowing exactly what i mean can post here the right way in english terminology to guide you.

Hope my answers are not only for your problem, as i try to make the techniques behind this problems generally and universal.

[mara-]

I'm sorry for going off-topic and majithia23, and sorry for using your topic, but why is "The two USB Cable solution is not an solution, its Manufators Crap". I would like to hear some arguments here. Thanks.

Cheers ;)

[majithia23]

@mara ,

no problem . continue .... ;)

on the same note , i havent seen an ext HDD with 2 USB cables , but yes i have seen ext DVD writers with such a set up ,

but no idea if its crap or actually useful !

@ApollonStar

thanks for the reply .

i ll check up with the manufacturer to see what the real power specs are .

and i did get the steps you mentioned regarding the " Optimize for Speed . "

but you see , i m on Win 7 , and such there is no straight forward option of " Optimize for Speed " .

Win 7 gives you two options ---

1> Quick Removal - Disable writing cache on the Drive and in Windows .

2> Better Performance - Enables write cache in Windows .

and i have the first option checked .

so i think it is according to what you mention in your post !

[dcs18]

Win 7 gives you two options ---

1> Quick Removal - Disable writing cache on the Drive and in Windows .

2> Better Performance - Enables write cache in Windows .

and i have the first option checked .

so i think it is according to what you mention in your post !

It's the 2nd one. :)

[majithia23]

@Rocketman

thanks for mentioning this .

but what i inferred from ApollonStar's post , he said to disable the write cache on device .

so it has to be the Better Performance , Enable Write cache in Windows .

[grouchysmurf]

First, thank you ApollonStar for the responses you made. Your english is just fine!

Ok, so here is a dumb question.......

Am I doing harm to my USB port by using an extension rather than using a powered hub?

I understand the power consumption versus available power to the channel, and adding in cable length

and the fact that my "extension" has its' own little "on" light, am I running the risk of fubar'ing my port?

As you answer this question, I am currently shopping for a "powered" USB hub device. ;)

[ApollonStar]

Thanks ALL OF YOU for your suggestions!!!

As i see theres still exists some confusion as to what all this is about and what exactly i mean.

You have to read carefully and then combine with the individual situation you are, of every USB set of problems everybody is. What i worte are universal guidelines, not for every topic, but still first to beginn with.

Thanks to RocketMan for his pictures. Thats it. But not always!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

-- As you see in the picture, the Button "Enables the write cache in WINDOWS AND NOT IN THE DEVICE CACHE"!!!!!!!!!!!!!!!!!!!!!!

-- Sometimes under other circumstances, depending on varius factors, there is another Button as you can have multiple choises, it depends!!!!!

-- Only then you see the choise to, "Better Performance" (Now i Know ;) ) and an selection you can make to enable write cache in Windows but leave the other, not a round button, empty, which says deactivate write cache on the "DEVICE".

-- So as i said, if its not there its ok, you only have to control the settings and if not already default for Win Vista/7, enable the Performance Option and Windows Cache. Thats it. And doent forget to Reboot and control again!!!

-- This is also the answer for the last question from Majithia23.

-- To answer Grouchysmurf (Man you have names here, i need a translator and new PC :rolleyes: ) YES, YES, YES!!! But be carefull, we all must commonly come together and agree in a Basic Terminology.

-- Two meters of Cable from your USB Port to your, maybe, USB Stick, is also an extension, so is an so called Passive USB Hub vs. an Active USB Hub.

A good Hub not only gives you power, from his own Power Supply, to the HUB, but also to the PluggedIn devices, and of course it reinforces, amplifies the signal Output from that USB Hub to your local USB Port back. So it can overcome the 1,5 Meters of the Cablelength specification. Up to what extent, who knows??? This can only be tested with special equipment and depends finally from the Chips the Manufactor used, the quality of the cable, bugs or no bugs, quantity of the attached devices, their interaction together and so on. Get the point???

-- As for Maras question, the answer is simple. The specs for an USB Port are at a MAX Output at 500 mA (Half an Ampere), with two cable which comes with most of the Pre Boxed 2,5" Harddrives, you can only have ONE Ampere MAX Output, but almost every such device requires more than that. To make things worse, the Manufactors do not tell such stories, in the majority of cases the 500 mA are for one Controler USB Chip of the Mainboard. Do the math!!! If you do not know, (assumed your mainboard has 10 USB Ports), which of them, in what order are for which controler, sooner or later you come near trouble.

-- Majithia23 wrote in one previous Post, that his manufactor has a higher USB Hub with Power Supply for P0wering 10 Ports at the HUB with 2,5 Ampere. Well maybe the Manufactor invented FREE ENERGY!!!!!!!!!!!!!!! Are they crazy????

-- Assuming i have pluggedin 10 Sticks and realy all of them in no circumstances pull, draw more then 500mA, and from Know-How and various Tests we know that this are rare conditions, than this would make 5 Amperes. What hell of a device!!!

-- Things get even worser with Harddrives, comming back to Mara, they pull much over their OWN SPECS, as in Bursts of PowerDRAW (READ-WRITE and parallel work), they explode in Power. To resume, Malfunctions in windows, such as throw out the device (Yellow triangle) with Data loss are common and has nothing to do with bad cables (These are single cases).

-- I`ve never in my life bought a Harddrive which comes pre Boxed from a manufacture and never will be. I always search for actuall HardCase and it must have a built in Fan, big, silent and high quality and than i choose my drive, combining the Controler of the Case and the specs of the drive in my reflections for the best outcome.

Man i could make your PC 8 to 10 times faster without hardware upgrade writing all this :showoff: .

-- As for what i wrote for the Formatting issue it still remains, but probably only for XP.

Lets see if i forgoten here somebody. OK.

Before you buy a Hub, make sure what and how much devices for what porpose you will use. If you make a choise contact manufactor to question him if this is technicaly possible. Which and how much Controlers are built in and how good is the device funktion if its OverPowered in overall consume. Can you put in all Ports of the Hub consumers simultaneously without trouble??? And then comes the million dollar question, all that Data comes together in ONE AND ONLY ONE PORT of your Mainboard. But thats another story!!!!!!!

Lets agree, USB HUB is not the paradise, but only a technical compromise and after 15 years of USB history, it is still a problem child!!!!!!!!!

Doent mess around with it. Know what you want, know what it can and cannot, know what it will be and know what you will have at the end.

Read Tests, read Magazines with technical articles, search google for guides and READ BETWEEN THE LINES!!!!!!!!!!!!!!!!!!!!!!

Good luck and best success to everybody.

[dcs18]

@ ApollonStar & @ majithia23

The screenshots were uploaded just to remove any (possible) element of uncertainty. Hopefully, new members who come across this thread might find it handy (and convenient.) :)

[grouchysmurf]

ApollonStar, Thank you for the response. I have shopped and found a nice powered hub

for little money.

You know, I do not recall an in depth discussion on USB hub vs extension. Maybe someone should sticky this?

[ApollonStar]

I appreciate every effort and help from every one here at this thread and of course also that from RocketMan.

[majithia23]

cool .

another great informative post from you buddy ! :)

to be honest , i did a quick surface read just now ( bit tired ) ,

but sure will again read in b/w the lines once i wake from a snooze ! :P

keep 'em coming !

[ApollonStar]

Hey Guys,

a suggestion, why not just write which of you have already a current HUB Model, with name, Company site, maybe Revision Number and how pleaced you are or which do you favour to buy.

Just interested me.