ok, first off, my laptop is custom built from ibuypower, i've had it for almost 2 years.

here's the problem that has started recently: I can boot with the battery, it loads and looks normal, until it gets to the login screen (windows xp home), at the login, it is just a black screen, the blue and my username does not show up, although i can move the cursor, because it does show, and i can click on my username type password in and press enter all like normal, i just cant see it, even though it loads, it still stays black.
when i boot with AC connected, it works fine, when i go to power options, it shows the battery having 100% charge, but after it's loaded with the AC, if i disconnect the AC, the screen doesnt go black, but it freezes, the cursor still moves, but nothing i click on loads, the only way to fix that is to 1. close laptop lid and let it goto sleep mode then plug in AC and open and press the power button, it works fine then, 2. force power shutdown (hold power button down) and reboot with AC plugged back in.

i just want it to work off the battery again, any suggestions as to what my problem could be and how to fix it? i've considered getting a new battery, but it shows this one as being fully charged.
o yeah, my batter is :
Lithium Ion Battery
MS 10XX Series
Rating: 14.4vdc

Hi there and welcome to PCHF, unfortunatly this is not my area of expertise. A tech should be along shortly.

Ok, thnx =)

does no one have any idea what's wrong with my laptop?

Ill notify one of the techs, i apologise for the delay.

up..maybe someone has a solution?

Hello Kmitsu, welcome to PCHF.

You can customise your brightness settings between when you are on and off charge to reduce power consumption. Whilst on battery, are you not able to adjust the brightness by holding down the [FN] key on your keyboard, and pressing the increase brightness key, normally the up arrow or [F8] key?