Question Too many USB devices causes BT to disconnect. Install Expansion Card?

[Hey_AND1]

I have a lot of USB devices plugged in to my desktop computer, including a video capture device, and this is causing disruption on my bluetooth-connected keyboard. Yes, to my surprise, I discovered that USB and BT devices share the same underlying bus.

My BT keyboard kept disconnecting and after weeks of troubleshooting I found the tree view on Device Manager:

After knowing this, I started unplugging USB devices and lo and behold my BT keyboard never disconnected again. Thing is, I want/need to have more USB devices plugged in to my PC and the bus seems to get saturated quite quickly, or the keyboard is a bit of a diva idk: plug in video capture, Keyboard starts disconnecting, unplug it, Keyboard never disconnects. I actually had this happen before but managed to solve it by shuffling around all the USB devices among the different ports until it reached stability, but now I want to add one more device and the problem reappeared.

I'm thinking of installing a PCIe USB Expansion Card WITH ITS OWN CONTROLLER.

• Do you guys think this is a good idea that would solve my issue?
  • What if I install a video capture card, thus changing from external/USB to internal? would that share the same bus and keep causing issues?
• Do you have any expansion card to recommend? must have USB-C, and I'd like to stay away from external ones as that would add more [vulgarity redacted] to my desk including a cable to power it.

Thank you!

Specs:

• CPU: Intel Core i9-12900K 3.2 GHz 16-Core Processor
• Motherboard: MSI PRO Z690-A WIFI DDR4 ATX LGA1700 Motherboard
• Keyboard: Keychron K10 Pro

 

[Lutfij]

BIOS version for your motherboard at this moment of time? As for your USB devices, can you list all of them? Your motherboard has headers for USB2.0 and USB3.0;

I'm sure you can get a breakaway bracket to hep expand on the USB ports native to the chipset.

 

[Paperdoc]

I wonder about power. Each USB2 port on your computer can supply power at 5 VDC up to 0.5 A max load. For USB3 ports, that limit is higher at 0.9 A. If you are using simple USB Hubs to connect several devices to a single port, then all devices on that Hub / port share that limited power supply. Too many devices on one port can overload it and deprive some of those devices of adequate power so they fail. The fact that you were able to "solve" the issue previously by juggling which devices were plugged into where MAY mean what you managed to do was re-distribute several devices' loads among different separate ports and avoid an overload on at least one port.

It can be difficult to find the exact current consumption specs of some USB devices, especially items like simple keyboards and mice that use little power. Specs for other items like desktop hard drives, Bluetooth transceivers and video capture units should tell you their needs.

If that is your situation, there is a simple solution. Hubs come in two basic forms. The easy ones have USB ports and that is all, so their only power source for the attached devices is what comes from the host port with its limit. These units often are sold as "bus powered", meaning their only supply is the USB Bus. The better ones come with their own "power brick" that plugs into the wall outlet and the Hub. This type provides all power to each Hub output port from that power supply, and draws NO power from the host computer port, so the port limit does not apply. For the Hub's ports the limit does apply PER PORT on the Hub. For the total load on all the Hub ports the limit is determined by the power supply module provided. For example, for a USB2 Hub, EACH port should be able to supply up to 0.5 A, and a powered hub with five output ports should have a power supply module that can supply up to 2.5 A at 5 VDC. However, you almost never see that. Why? In practice it is common that NOT all ports on a Hub are in max use simultaneously, so a lesser power supply module usually is sufficient. Personally, I consider that the power supply unit that comes with a powered Hub should be able to supply at least 60% - much better 70% - of the theoretical max. So for a USB2 Hub with 5 ports, the power module should be capable of 5 VDC at up to (2.5 x 0.7) = 1.75 A. For a USB3 Hub that is supposed to supply up to 0.9 A per port, a 6-port unit should have a power supply for 5 VDC at up to (0.9 x 6 x 0.7) = 3.8 A.

Now, there are two factors that make this slightly more complicated, One is that many Hubs, especially among USB3 Hubs today, have extra "charging ports" (most of which do not function for data transfers but work only for charging) that can supply much more than the 0.9 A per port - as much as 2.5 to 3.5 A on those ports. If you are not using such ports, this makes no impact. But if you DO plan to use them for high-current changing, then these ports need to be treated separately from the normal data ports and their power needs added in to the Hub total. This impacts the power rating required for the included power supply module.

The second is that in so many such units on the market the power supply module output is at 12 VDC, and the Hub itself converts that to 5 VDC for its output ports. In this scenario you need to do all the power calculations in WATTS, where Watts = Volts x Amps. So you take the Volts and Amps of the power supply module and multiply to find its Watts rating. Some units provide that info in their specs. THEN you re-do the calcs for each Hub output PORT. For USB2, each port should output 5 VDC at up to 0.5 A, or 2.5 W max PER PORT. For USB3 Hubs that is 5 x 0.9 = 4.5 W per port. Count up the ports and use the 70% de-rating to get total max power needed from the power supply module. HINT: in choosing a Hub, sometimes buying one with more output ports than you really need is good becasue the larger unit comes with a higher-rated power supply module you DO need.

IF several of your user devices are designed for USB3 and IF you do have USB3 ports on your computer to use, there are two advantages to getting a USB3 Hub. First, it CAN provide the higher max current per port those devices may need. Second, the max data transfer rate for USB3 is TEN times faster than USB2.

Just a small note on names. I used the term "USB3" above as a generic label. In fact, the proper current naming is that all USB3 systems are called USB 3.2 Genn , with three sub-classes. Gen1 units can do data up to 5 Gb/s, Gen2 can do up to 10 Gb/s, and Gen2x2 can do up to 20 Gb/s. Earlier names may have used USB 3.0 for Gen1 and USB 3.1 for Gen2. USB 3.2 HUBS today almost all are Gen1 devices, but some Gen2 Hubs exist. I have not yet seen any Gen2x2 Hubs. In the older USB2 system, almost all units on today's market will be the last iteration of them able to work at 0.48 Gb/s.

CABLE / CONNECTOR notes. We are familiar with the USB2 common rectabgular socket and male connectors called TYpe A. These have black plastic inserts in them that support four contact strips. The USB 3.2 version of these look very similar but they have BLUE inserts in them (or some other colours) and include those same four contact strips PLUS five additional contacts on the front edge of the insert in the male plug. USB 3.2 Hubs etc. CAN work with USB2 units, but at the USB2 slower speed, of course. For any actual USB 3.2 device (icluding the Hub) you MUST use the newer USB 3.2 style of cables and connectors to enable full USB 3.2 performance. In fact, IF you are connecting USB 3.2 Gen2 units, you really should be using a different cable type with the newer Type C connectors.

OP, if you need help figuring all this out to get all your USB devices connected with adequate power, post a list of all those devices with model numbers if possible, or any Volt and Amp or Watt specs they show.