The usb myth

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I have 20 ZIotek Carousel's running trough 4 powered 4 port USB 3 4 amp hubs and one 13 port USB 2 3 amp hub, and I was using a ASUS Striker Exstreme/NSE II board and it was detecting all of them and would reconfigure if I plugged another device in. So I decided to update my system with a ASUS Z87-Plus motherboard and a i7-4770k processor and now can't get more then 7 of those devices attached. These Carousel devices are sold with the idea that at lease 127 devices can be attached in series on one root hub as while as many other such devices and that is the myth. Is there anybody out there who has successfully attached any wheres near that out there and how did you do it? I'm running W 8.1 on this machine
 
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bjaminnyc

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Wow, that's quite a content setup. Sorry I never tried to connect that many USB devices of any nature.

Out of curiosity would you mind sharing what the setup is for? TV or Radio?

If you own the content may I ask why you wouldn't just store everything on a RAID array vs the Carousels? I'm guessing you have a logical reason based the complexity of your rig sig.
 
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Each device is powered on its own and the hubs are there to make sure that happens.
 
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When it comes to what you love is there any logical reason to do what you do? In my mind I have the DVD's or BD 's and and like to go back and watch them on my BR player when I want, and I started this a few years back strictly for Movies I own.
 
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ex_bubblehead

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The USB bus is limited to 127 devices per controller. This seems like a lot, but it is important to remember that hubs count as one device, and the root hub also counts as a device. So, consider a tree of USB hubs and USB-serial adapters. Let n be the number of ports per hub, k be the number of hubs in the tree and r be the number of USB-serial adapters. This gives us a total of n * k ports. To connect the k hubs in a tree we require a minimum of k – 1 interconnects, so the maximum number of USB-serial adapters is r = nk – (k – 1). Because there is a maximum of 126 devices (127 minus one for the root hub), in the best case we have k + r = 126. Solving for nk yields two equations, nk = 125 and r = 126 – k. When nk = 125 does not have an integer solution, it is best to round k up; otherwise, less than the maximum number of ports will be available. Consequently, with four-port hubs (n = 4) we have k = 32 and r = 94, for a maximum of 94 USB-serial adapters on a single controller. With seven-port hubs, k = 18 and r = 108.

You may very well be exceeding the limit of the motherboard. At any rate, the practical limit is usually reached at only a handful of devices per port due to bandwidth and power limitations.
 
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on the striker board there is one root hub and all the devices worked, on the z87 board there is 3 root hubs and only one third of the devices work.
 
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Yes thats when I had 15 now I have 20.
I use three programs for different reasons, the software that comes with the Carousels, DVD profile for reports, and Collectz for managing my collection on my iPod touch.
 
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