- Joined
- Sep 28, 2020
- Messages
- 76 (0.05/day)
I have a wierd issue with 2 equal laptops - Lenovo T480. 1 of the laptops lasts 7:30-8:00h, the other one always lands at around 5:30. So far i have done over 20 head to head tests, and tried everything possible. Both run the same firmware, bios, etc. It's an idle test with wifi off and screen at maximum. Both run the same ram stick. I time the run time by using coretemp's logger. Both have practicaly the same average temperature and average cpu usage and same average frequency.
So far i tried:
1) switch SSD's between them
2) switch batteries
3) switch screens
The only thing i can observe is that while both idle at same frequency and temperature, they dont idle at same voltage. The better laptop idles at 0.63V while the worse idles at 0.73V. Thats a whooping 0.1V at idle and far more than i ever saw on laptop. Since i switched their SSD's to take that out of the equation, the only thing that comes to mind is worse silicon lottery. But that is a huge difference !
Maybe someone saw something similar and knows if there is some other issue i am not aware of. Because 7h30m vs 5h30m simply because of silicon lottery that is a really big difference. And apart from motherboard and cpu, i took everything else from the equation.
So far i tried:
1) switch SSD's between them
2) switch batteries
3) switch screens
The only thing i can observe is that while both idle at same frequency and temperature, they dont idle at same voltage. The better laptop idles at 0.63V while the worse idles at 0.73V. Thats a whooping 0.1V at idle and far more than i ever saw on laptop. Since i switched their SSD's to take that out of the equation, the only thing that comes to mind is worse silicon lottery. But that is a huge difference !
Maybe someone saw something similar and knows if there is some other issue i am not aware of. Because 7h30m vs 5h30m simply because of silicon lottery that is a really big difference. And apart from motherboard and cpu, i took everything else from the equation.
