I’m looking to replace my sff J5040 Wyze machine. Its still plenty fast enough, but storage has become an issue with its limited USB endpoint availability of ~50 device limit.

I know that just switching it up to a newer Intel system could give me double the endpoints because of the two XHCI chip setup, but I was thinking that if I’m going to replace it, I’d like to not limit myself.

As such, even though Ryzen is far faster than I need, it does now support USB4. Does anyone know if the switch to USB4 would give the system a larger address range and have more than 127 USB devices or is that limitation still in place and I might as well not waste my money?

  • catloaf@lemm.eeEnglish
    7·
    7 months ago

    A quick Google does not produce any results showing an increased device limit.

    I’m curious, what are you doing to reach 127 device endpoints, especially on a thin client?

    • frazorth@feddit.ukOPEnglish
      1·
      7 months ago

      I’m not. Intel does not let you get that high.

      https://community.intel.com/t5/Embedded-Intel-Core-Processors/Hardware-limitations-on-USB-endpoints-XHCI/td-p/264556

      From Intel.

      First Limitation

      Fundamentally, the customer is correct. You will never be able to achieve 127 actual USB devices attached to a Host Controller (i.e. Intel system). As the customer pointed out, each USB device (USB key, keyboard, mouse, etc.) is typically counted as two endpoints (two logical USB units), and each USB hub, multiplier, or repeater is counted as another 4+ endpoints. So, it comes to about 50+ devices per each Host Controller.

      With these systems it was only 25 devices total (unless you use hubs), so they introduced two controllers to allow 100+ endpoints.

      It’s because of this reason that Intel added a second USB Host Controller in the majority of its Core platform chipsets. If you look at the Features page of the 8 Series Chipset ( when partnered with the 4th Gen Intel Core processor), page 39, http://www.intel.com/content/www/us/en/chipsets/8-series-chipset-pch-datasheet.html http://www.intel.com/content/www/us/en/chipsets/8-series-chipset-pch-datasheet.html, it states having “Two EHCI Host Controllers, supporting up to fourteen external USB 2.0 ports”. So, with two Host Controllers, each at 50+ device, you have a potential of connecting up to 100+ USB devices per 4th Gen Core platform system.

      And thats not considering the internal hubs that split back and forward ports.