I have a Dell 7400 laptop. I used to use it daily for 10 hours, mostly on battery. I would charge it throughout the day as needed, and would get around 3-4 hours out of it before it needed a charge.
then one day i noticed it started to drain the battery much faster. it was like this for a week, i had to throw it on a charger every 90 minutes.
we had some 7400 at work, so i yanked a battery out of a unit that had low SSD hours. it was a higher capacity battery. it did not make a difference, the battery still drains quite fast.
running windows 11, i never reinstalled the OS, maybe it was some os update fucking things up? its been over a year since this happened and this new battery still wont last long. i dont use this laptop much anymore. i dont think i grabbed a bad battery either, the ssd had 448 hours on it.

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