Why does my laptop screen brightness goes darker when i unplug my battery charger?

And then whenever i plug in my battery charger the screen goes bright again, i searched on google for the answer but none seems to work, i went to control panel, more power options, etc. And everything. And i just got my laptop today or a few hours ago. And also I'M NOT a professional when it comes to laptop or computer problems.

Added (1). And I'm using a Lenovo. Windows 8, i don't know if that has to do anything with this but k.

Added (2). ALSO, what do i do to stop making my brightness go dark when i unplug my charger?

Lenovo Laptop: Yoga 3 VS Thinkpad Yoga?

I'm looking for a new laptop and these are my two choices. What are the pros & cons of getting one over the other?

Trying to buy a video editing laptop and I can't choose which one I want?

After a 3 month search i've finally narrowed down my laptop choices to these three:
1. http://www.frostsupermart.com/asus-rog-gl551jm-dh71-156-gaming-notebook-intel-core-i7-4710hq-16gb-ram-nvidia-geforce-gtx-860m-2gb-1tb-hdd-windows-81-428-p.asp

2. http://www.ebay.com/...EBIDX%3AIT

3. http://www.ebay.com/...1624467096

I'm in college so I can't get a desktop, and I need something in the 800 range because i'm on a budget, all of these laptops have all the components I want I just don't know which one is the best out of the bunch

Why is windows 10 not working properly on my laptop?

My processor is 2.5Ghz core i5. Ram is 4 gb. I upgraded from win 7. Now it doesn't work right. Some time the laptop goes crazy. Cortana isn't responding. Sometimes the Keyboard and touchpad arent responding. The interface looks nice though. Help!

Added (1). Its a 2nd Gen Lenovo

How to return my stretched Windows Xp screen to normal?

How to return my stretched Windows Xp screen to normal? - 1

Added (1). I didn't even press anything to my knowledge; the screen is just suddenly stretched out of nowhere. In addition, sounds (Youtube videos, notification sounds) do not play normally anymore. I can't find any usable information on how to fix this problem. I use a Lenovo laptop that runs on Windows XP.

My lenovo laptop's language is in china language, how can i change it into english?

My lenovo laptop's language is in china language, how can i change it into english? - 1

Will this computer run minecraft smoothly (no lag on max settings)?

http://www.currys.co.uk/...4-pdt.html

Added (1). laptop*

My lenovo 3000 N100,it immediately starts heating when turned on,& shows Operating System not Found

I have a lenovo 3000 N100, whenever I start this laptop it immediately starts heating up and on the screen just the Lenovo Banner appers, Windows is not starting and message appears "Operating System not Found"

I have shown this to some hardware engeniers no-one is able to find what the matter is, I have not gone to the Lenovo Service Center because I think they will charge some heavy fees for this. Therefore i would request in this forum if someone can guide me for this issue.

Can this laptop handle these games?

I may be getting a laptop and I was wondering if I could play these games on it even if in low or medium quality. Lenovo laptop a8 6410 processor, 4gb ram, 500gb HDD, quad core, amd radeon hdr5 graphics card.
I'd like to play:
Minecraft
Skyrim
Fallout 3 and new Vegas
Cod waw
Garry's mod
Guild wars
Any help would be appreciated and if it makes a difference I may get an 8gb ram. Also what specs would you recommend for these games?

Will windows 10 automatically update your system with correct drivers from the device manufacturer?

Fter windows 10 upgrade i tried to install intel hd graphics driver downloaded from lenovo website (i have a lenovo laptop) , but while installing a message came saying my present driver is a higher version already. I'm confused, please help.