Hardware: HP EliteBook Revolve 810 G1 with Ubuntu Linux - problems

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Warning: I no longer use this laptop as my primary device (April 2016). Therefore this page is no longer maintained and may become outdated.

This page describe problems observed with "HP EliteBook Revolve 810 G1" during regular usage or tests.

Wireless

There is something wrong with WiFi scanning or network manager implementation. When I log in then device scan for networks and connect to my home WiFi. If there is need to do scanning again (for example when I move laptop to different place) then it looks like scanning is not invoked at all. GUI show stale entries and connection is not established.

Workaround:

sudo iwlist wlan0 scanning | grep SSID

Sometimes it is necessary to invoke this command twice. Then suddenly GUI found WiFi and connect to it.

I think network manager is not invoking scanning properly but it will need more in depth investigation.


Additionally from time to time network manager is not started at all.

Workaround:

sudo service network-manager restart

This is again pointing to network manager. More in depth check needed.

USB

This laptop have two USB ports. One is equipped with offline charge capability (e.g. you shut down laptop and you can still charge connected device). There is configuration option in BIOS which can configure cut-off percentage of battery. When battery capacity drop under this percentage then output is cut-off (to preserve power for laptop itself). Default configuration is 10%. I configured 50%. This port have following problem:

There is power glitch on USB port equipped with offline charge capability when charge level of main battery cross threshold. This can be during discharge of main battery or during recharge from mains.

This glitch cause restart of connected device. It may not be noticeable for HID and other kind of devices but cause file system corruption on USB Flash and HDD devices.

Workaround:

  • Use second USB port for devices which should not lose power during operation.
  • Disable feature in BIOS

It is not mentioned in BIOS release notes but I try to update bios to see if this help.