Talk:Lenovo ThinkPad T490
Is there an actual problem with Bluetooth? It works fine for me: pairing, initial connection and subsequent connections. Neither I have the debugfs warnings anywhere in the logs.
Melentye (talk) 13:06, 31 January 2020 (UTC)
Mobile Internet
Mobile Internet is marked as not tested. I can confirm that internal FIBOCOM L830-EB LTE modem works all right; I have created a Linux script that utilizes systemd and mbimcli to start and stop the connection. Feel free to use it.
PetrKutalek (talk) 17:04, 13 March 2021 (UTC)
Sound and mic stop working on Lenovo T490 after a while
I set my laptop to go to hibernate after a while following the recommended settings in GNOME#Power. However, I ran into the issue described in [1]. I now disabled hibernation again and am looking if that fixes the issue. If that fixes it, it probably makes sense to include this in the Troubleshooting section. Has anybody else experience with that issue as well? Jaudriga (talk) 10:23, 1 April 2021 (UTC)
Update GPU section
In my own testing, bbswitch is not a great solution. It doesn't work at all if some program such as GDM locks the nvidia drivers, and changing and experimenting takes a lot of trial and error and changing of system files. It's also really old.
Other solutions are not ideal: envycontrol prevents suspend on integrated mode, and nvidia's built in power scaling solution isn't nearly good enough.
The solution I've reached is using direct acpi calls to turn the gpu on and off, bypassing systemd completely. It doesn't seem to affect suspend negatively.
I use the commands
echo '\_SB.PCI0.HGOF' > /proc/acpi/call
and
echo '\_SB.PCI0.HGON' > /proc/acpi/call
to turn the dGPU off and on, respectively. I got the function names from this article.
I'd like to check with other owners before updating the page.
Jabcross (talk) 21:49, 10 May 2023 (UTC)
- Yes, this seems to work on my T490. Bbswitch used to work for me but I'm now randomly getting high power consumption. Maybe that's due to a BIOS update I did at some point.
- NOTE: the reported power state in /sys/bus/pci/devices/0000:3c:00.0/firmware_node/power_state is no longer reliable with this – but I've got the feeling it's not reliable with bbswitch either.