I recently took apart a dell dimension 3100. After assembling correctly and carefully, the on board vga doesn’t work. I had to borrow a graphics card from another computer for it to work. But I would really like to see the on board vga work again so I don’t have to buy another graphics card. With the on board vga, it would just show the monitor with green and grey bars all glitched out... I have no idea what to do. Please help me if you know anything about this. Thanks!