Let me start with a common laptop battery spec. "300 cycle rating." which means that the battery is still considered good if it holds 50% capacity after 300 cycles.
-> So the BIOS could call the battery good if the capacity is 50 or more percent from new. But that may not apply here as you are writing about Windows, Updates and the fan is kicking on.
We know that updates can cause Windows to use more CPU time and power. Linux seems to not do that so a move to a more stable OS can be the fix here as it's up to you to find what app or service is using the CPU and adjust if you can.
There is no answer to your issue because there is no single cause or cure (besides Linux.)
Hi, everybody
When I bought a laptop, it had a battery life of 7-8 hours, but after some recent updates, its battery life was only 2-3 hours, and it got very fast. According to the BIOS, the battery is in good condition. When idle, the power consumption of the CPU is really high. Even if the CPU load in Windows is only about 1%, it is only 8-9 watts. I have tried running the \ live version and the laptop is absolutely quiet, cold, and shows about 8 hours of working time in Linux. I have reset Windows to the factory default settings and it consumes the same amount of power even with a new Windows. When I type this message, the laptop activates cooling every 30-60 seconds, with only 2-3% load. I've thought that maybe some security updates broke processor optimizations for some operations. Exhausted all possible ideas. Maybe someone has similar experience, found a solution or have some ideas.
Thank you.

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