Re: Laptop shut off last night after...
It's possible that your AC adapter failed and your system was running on battery until it finally ran out and shut down. It's also possible that your AC jack has become disconnected from your motherboard (that would require a simple solder job to fix).
A few things to test:
Try unplugging the battery and plugging in the AC. Does plugging in to AC light up any of the LEDs? If not, it probably means the AC adapter is dead (either that or you have major problems like a dead motherboard or broken connector).
Does jiggling around the AC plug (where it connects to the laptop) make it light up? If so, you may have a lose jack requiring a solder job.
You should check your AC adapter first, since this would be the least expensive and simplest to test. Even if you had a short that fried something on your motherboard, your laptop should respond with blinking LEDs or beep codes unless it's a power related failure (preventing beep or LED codes or power on attempts).
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