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i dont have much time to write this as my battery will die any minuitre but heres the basics;

im not sure what laptop i have but i THINK its a D350

its a buisness type and runs on vista

basicly my screen has been a bit weird lately and a certain section was blacking out but this morning the whole screen has gone a really dark black and its really hard to see the screen, if i turn the laptop off, unplug the charger and turn it back on, i can see the screen perfectly but as soon as the chargers plugged in it goes dark again, ive checked the button on the battery to make sure its charging and it is, i tried the charger in my step dads laptop and it works fine. since i had the black screen when i turn the laptop on the lock with the number 9 is always lit up. i need to fix this as soon as possible as all my college coursework is on here and i dont have enough time before the laptop dies to copy the last file to a memory stick as its 6.8 gb. please help!