Network Problem Solved by Powering Pi from USB Hub

[exartemarte]

Powering the Pi from a powered USB hub was discussed early on, before most of us actually had a Pi, and was deprecated by some. It works for me, however, and has solved a problem.

With the hub connected to the Pi, networking ceased to function in LXDE – a problem experienced by others and discussed in another thread. This was variously attributed to ill-defined "power supply problems" and the hub's Genesys chipset – also discussed elsewhere and said to cause compatibility issues.

But when I dispensed with the Pi PSU (UK sourced, rated 5V/2A and delivering 5.24V to the Pi via Kindle charger cable) and connected the Pi's power cable to the hub instead, all the problems went away. So now I'm wondering whether the problem is not so much inadequate power supplies as multiple power supplies, which will inevitably supply slightly differing voltages.

For the record, my current setup is:

• Wireless Ethernet bridge connected to Ethernet port
  Hub and self-powered HDD connected to Pi USB ports
  USB memory stick connected to hub
  PS/2 keyboard and mouse connected to hub via Belkin adapter
  Pi and Ethernet bridge power cables connected to hub
  Breadboard with LEDs, etc, attached to gpio connector.

It all runs from the hub's 5V/3.5A power supply, which is convenient, and it all works. It's been like that for about three weeks now and seems stable and reliable. Which means I can get on with doing interesting stuff with SSH, Samba, C, Python and the breadboard instead of spending my time just trying to get it to work.

I'm rather pleased about this – not just because it works, but also because the hub, a seven-port one retired some years ago because it wasn't a convenient shape for my desktop, is exactly the right size and shape for the Pi. It's flat and slightly larger all round than the Pi, which sits happily on top of it secured by Blu-Tak and connected by conveniently short cables found on eBay.

[3mek]

Hi, maybe you can reveal what is the hub producer / model name. 3.5A power supply sounds really nice.
cheers,
Simon

[exartemarte]

It's a Mikomi 7-Port Hub, Model No UH-GL1S, but I've had it a long time and I don't think it's a current model. You can see it in the picture, underneath the Pi. It's a silver-grey plastic box with four ports on the front and three at the rear. The upstream port and power socket are on the left-hand side.