7520 15R SE - Battery

I bought the 7520 last spring and it seemed the battery took longer and longer to charge over time. And getting less use out of a full charge. So I called Dell last week and they sent me a new battery (wasn't that much of an improvement).

But since I got it, I've been having issues with my power options. I had my screen brightness settings set to 10 with it plugged in and 10 on battery. And I never had a problem with the screen brightness switching from plug to battery.

But ever since I got the new battery last week, the brightness setting goes down to 4 or 5 all by itself. So when I pull the plug out, the screen dims. Not a big deal - I can brighten the screen - but it shouldn't change on its own.

I also had trouble with my closing the lid settings. I didn't want to have to enter my password, but it kept asking for it when I lifted the lid. But finally I think that worked itself out.

I called Dell re: the screen brightness issue and was on the phone with them for almost an hour. Most of the time was showing him (he connected so he can view my screen) what was going on. And he kept saying, "when you pull the plug out using "'power saver'" (which is what I had it set to), "it will dim."

But I kept telling him that I never had a problem like that before. Pulling the plug out and going on battery never dimmed my screen because both settings were set to 10 ever since I got the laptop.

I tried this with the old battery and the same thing keeps happening.

He mentioned the BIOS driver, but I had already done that.

I *think* he finally understood and he's going to take it to tech support (on my request) and will get back to me.

But I'm wondering if anyone would have a fix to this. I asked for an uninstall and reinstall of the entire power settings, but he said that couldn't be done.

Two things worth mentioning.

1. When I was on the phone with the tech and showing him what was going on with the power plan options window open - at this point I moved the power plan to "Balanced," with the brightness set to 10 on both plug and battery - when I pulled the plug out, the dot moved from Balanced to "Power Saver" by itself and the screen dimmed to 4 or 5. And a check of the settings within "Power Saver" it had moved down to 4 or 5. And it was set to 10 (and yes I do click "save changes" after each time I re-set it to 10). So it is moving by itself.

2. When I got the battery last week, it had 0% power. So I plugged it in to recharge (while using the laptop). But it stayed at 0% for hours. I think I might have turned the laptop off and kept charging, but that didn't boost it from 0%. So it took a long time for it to start charging.

Both batteries are the Dell 48wh