08-06-2019 12:59 AM
I was wondering if anyone has experience with the battery life of the T490 under Linux, especially Arch.
In reviews I'm reading something between 8 and 10 hours, but I guess that's when using Windows.
Is this true?
I recently bought a T490, and while using TLP, and measuring between 8-10W usage in powertop, I only get around 5-6 hours out of my unit, with light use.
When using more demanding apps like Firefox (especially Youtube), battery life drops to 3-4 hours.
TLP is in use, Nvidia kernel modules are disabled (the MX250 is unused) and I just want to know if this is normal?
08-27-2019 02:19 PM
08-27-2019 10:52 PM - edited 08-27-2019 10:54 PM
I wasn't expecting any response any more to be honest, but I'm happy that there is someone who noticed the problem too.
Being totally aware that the listed battery hours are measured in a laboratory, I'm still very disappointed that they are so far off.
For now I switched to Windows 10 which is a shame. The whole experience really sucks. The device apart from the battery is nice thought, which is why I decided to keep it. Battery live under Windows 10 is considerably better than any linux distro I've tested. I'm at least getting something from 7 to 8 hours.
What you have to keep in mind is, that they are advertising 16 hours of battery life for the T490. If I fully charge my T490 and dim the display to the lowest (not off), in power saving mode, doing literally nothing, I will max out around 11 to 12 hours, so I feel like being lied to.
It's a shame that battery life under linux is so bad. I would be happy to at least get to know a reason for this, so I can understand it.
09-19-2019 07:50 PM
09-20-2019 12:37 AM
The MX250 was the guilty one, yes. I'm sure you can definitely make it work somehow, but what's the purpose of a dGPU in a laptop that you can't use because it drains the battery.
I ended up returning the T490 and went for a X1 Carbon.
I have a really good battery life now with power consumptions between 3 and 8 watts.
09-20-2019 01:15 AM - edited 09-20-2019 01:16 AM
I want to preserve lightweight gaming support, so therefore I will not return my T490.
I'm hoping that nouveau or nvidia drivers will eventually support RTD3 correctly. Nvidia already announced support for RTD3 in their proprietary beta drivers, but annoyingly only for Turing cards
One option though is that Lenovo will support disabling dGPU in BIOS. There is already a request for that asked here.
09-23-2019 04:28 PM
This solution seems to work fine for Ubuntu 19.04:
09-23-2019 08:23 PM - edited 09-23-2019 10:45 PM
For me, the solution in Pop!_OS discussion is not working perfectly. Even though blacklisting some of nvidia modules, the driver doesn't want to set the GPU to lower P-states than P8. This is not ideal: putting it to OFF should be the best option and P12-state the second best.
Pop!_OS solution puts the card to jump between P0 and P8.. at least on boot, it is P0 and then it drops to P8. However, I managed to get it to constant P8-state by adding this.
$ cat /etc/modprobe.d/nvidia.conf options nvidia NVreg_RegistryDwords="OverrideMaxPerf=0x1"
But do you get the card to state P12? You can check it by nvidia-smi (below the card name Geforce MX250).