My mini has had power problems for a long time. The battery is dead and when it was plugged in the white light would be on but the battery never charged. What would happen is: I would press the power button and it would start to boot for about 7 seconds and then shut down (Windows XP). I tried pulling the battery and holding the power button for 40 seconds that did not help. I did notice that when I went into the bios it would stay on much longer before it would shut down. Yesterday, I took it all apart and and just reseated the memory, put it back together and after a few tries it actually ran for 3 or 4 hours, I updated windows rebooted it booted up fine. Then out of the blue it shut down and now I don't get any lights. I tested the power supply and it is fine, I checked from the power connector to the power lines inside and that checked out normal. Any idea's or advice on what to try next? I did take it apart again and reseated the memory again, no luck.