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USB - Powered hubs or USB cards?

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I am trying to put together a cockpit that has 15 USB devices.

 

I seem to have some issues with windows or FS finding various devices when they are hooked up to USB hubs. (I have 3 powered hubs).

 

I already have one USB card in my PC, should I press on with the hubs or should I but another two USB cards?  

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It could be a "power" issue. I do know that successfully running multiple devices off a USB hub is largely dependent on the amount of power they require. What I don't know is how much power your powered hub(s) is capable of delivering. There must be a spec somewhere for the hubs as well as specifications for each device requirement.

The same goes for the cards. They take their power from the power supply that is built into your computer. This could be done by supplying the card with 12 volts, then separately supplying each port with 5 volts. However, there is a finite amount of power available from your power supply. Exceeding that might cause the problems you're experiencing.

I ran into a problem where I wanted to supply a 4 port hub with DC from the computer power supply instead of the household lines plug/transformer that the hub usually uses. I was running out of lines plugs in the vicinity of the computer. Strange things happened and the local computer guru slapped my wrist and told me not to mess around in the guts of the thing. Probably good advice.

I realise this is not answering your question, but the hope is that it will help direct your thoughts to issues you may not be aware of.

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Also John, I would look at the problems with USB2 v USB3, as some things are not USB3 compatible. Especially Saitek stuff. They need USB2.

If you have room in your case and Mobo, I would get as many USB cards in as will fit.

Hope you sort it.

I have had a nightmare sorting mine out but seem to be stable now that I've realised the 2 v 3 issues.

Good luck.

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I think it could be my PSU.  It is just a basic unit and I think it is overstretched.  Another thing on the Christmas list then.!

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I think it could be my PSU.  It is just a basic unit and I think it is overstretched.  Another thing on the Christmas list then.!

 

  :(  Hang in there JG

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It seems to be a power issue.  Thin down the number of USB devices and all is well with those still connected.

 

I feel an 850 watt PSU coming on!

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I think it could be my PSU.  It is just a basic unit and I think it is overstretched.  Another thing on the Christmas list then.!

 

 

I'm no expert on USB hubs, but are you sure?

 

You said you had three powered hubs, if so I wouldn't have thought your PSU was the issue. The powered USB hubs are powered from the mains aren't they, so not the PSU?

 

 

I'd be surprised if "one" USB card was too much for your PSU. What's the PSU specs?

 

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The issue I have is that some devices don't seem to be recognized if connected to a hub - powered or not.  If I connect them directly then they can be seen, IF I don't have too many attached.

 

I currently have thee powered hubs, each has seven ports, but if I overload these I get a problem that manifests in the same way as if I have too many direct connections.

 

I am trying to connect:

 

1 x keyboard

1 x number pad

1 x trackball

5 x Saitek panels

1 x Saitek Yoke or X55 joystick

1 x Throttle Quadrent (not used for throttle)

1 x X55 Throttle 

1 x Saitek Rudder 

1 x USB Monitors

3 x Arduino cards

 

That's a total of 16 devices running concurrently, 17 if I can connect the yolk and joystick at the same time.

 

3 devices are in a slid-away side panel cabinet and so they must connect to a hub in the cabinet the keyboard and mouse connect directly so they are available on boot, so that brings it down to 12 direct connections (one is the cabinet hub) or two maxed out 7 powered port hubs, or combination there of.

 

The maxed out hubs option doesn't seem to work so I think my next move must be to up my PSU (Currently 450 watts, which I probably need to anyway) and to add a few USB cards.

 

However adding USB cards will only give me 8 external ports as I have room for 2 cards only, so I will still need at least one hub. - unless someone can point me at a USB card that takes up 1 slot and provides more than 4 external ports.

 

 

 

 

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My thought on USB-connected Flight Sim add-on devices is that it's possible to have either of two problems, or both at the same time.

1) A computer's USB port can only supply 200 mA of current, no matter how many devices you have connected to that port through one or more hubs. As the current draw of the connected devices approaches the ability of the port to supply the needed current, the devices are going to begin to see anomalies, probably a voltage drop, and you can expect one or more of them to begin to act up or drop off line.

2) The other problem is simply bandwidth. Though I don't know the numbers, a single USB port to the computer has some limits to the throughput it can handle. Connect too many devices to a single port and there will be dropped communications, errors, or other issues. It's likely too that USB-connected devices communications footprints will not all be equal - some will require a lot of bandwidth and others not so much.

Powered hubs are the obvious solution to problem #1. In those hubs, the power supply for the connected devices comes through an independent connection to your home power, generally a wall transformer, and the computer port does not have to supply any of the power the devices need. That's a nice solution for problem #1 but does nothing to address problem #2.

The problem with a hub, powered or not, is that all the communications for all the connected devices has to go back to the computer and be handled by that single port. The solution to that is to distribute your USB connected devices across as many of the computer's USB ports as possible and to be sure that USB 3.0 devices, if any, are connected back to the computer through a USB 3.0 cable to a USB 3.0 port on the computer.

I suspect that for those with a large number of physical USB add-on devices, some combination of the two, i.e. using powered hubs and as many USB ports on the computer as possible is going to give the best chance of being problem free. Because of differing communications footprints between the various devices, just mixing up which ones are connected to which hubs and ports might also result in a better configuration. Two communications-hungry devices connected through the same hub might work better if each was connected to a different port or hub.

This is more of a common sense approach, not anything I've done physically, because I only have a half-dozen or so USB devices connected. However, from a logical engineering perspective, it just seems to make sense. All the devices have to have an adequate power supply AND each has to have good communication back to the PC. Addressing both of those is going to get the best result. It may well mean more than one powered hub in some cases.

John

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Wise words John. I guess I have too many devices on to few ports. 

 

I have just ordered two 4 port usb 3.0 cards. these are powered by their own molex connection. I know I don't need USB 3 but the price difference is minimal, and with backward compatibility, it seemed better to buy future proofed cards.  

This will give me 8 ports plus the MB own six ports 2 x usb 3 and 4 x usb 2), so I will have 14 ports, 4 usb 2.0 and 10 usb 3.0.  That should be enough!  I will hold off getting a new PSU at the moment to see how I get on with the new cards, as 450 watts is a mid range PSU anyway.

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 these are powered by their own molex connection. 

 

 

Not quite sure what that means.  Do the new cards have their own power supply independent of the computer's PSU or do they depend on the computer to power them?  If the latter, you might still have a problem.

 

That should certainly eliminate any bandwidth problems.

 

John

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The cards take power from the psu and not the motherboard.

I am no longer sure that the psu is the issue. The cost of the usb cards is a fraction of the cost of a new high end psu, so first I solve any potential bandwidth issues.

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from my experience you will need to go to a powered hub, because most motherboards cannot supply enough electrickery to power more than a couple of cards however it may also be the main power supply at fault I have an 850w power supply and before fitting it I did have the odd usb connection being lost,

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