whenver i try to plug my charger into my dell inspiron 1521 after 2 minutes it makes the screen go really really dark, i can faintly see the screen. why is it doing this for? when i havent got my charger plugged in it still does it but only after about 15 mins. it even goes dark if im in the bios settings or trying to run a format on my C drive. Basically im buggered. ive checked my connections to my motherboard and everything is fine, could it be my video card? but why should my power cable have anything to do with my screen going dark? the brightness setting is up to 10, the brightest it can get. Please can someone help me.