Now, first make sure that the power adapter / cord is fine and is giving right output voltage. If the adapter is broken it will not charge up the laptop and so you can see this behavior. Same thing can happen if the power jack in the laptop is broken.
Only when its confirmed that power adapter and power jack is not bad, do as stated further.
What we just did is, we drained all charge from your motherboard. But it still didnt work.
Now you can check these things :
1. Try re-inserting the RAM (memory modules) - do this first. Ram is located on back of laptop under a lid and you will have to open couple screws to reach it.
2. Bios battery. It is a button type battery located on the motherboard inside your laptop. Replace it with new one.
If this doesnt work out than its possible that the BIOS has got corrupted. You should get it flashed by taking it to some repair shop.
If this doesnt work, than your motherboard or ram is damaged. You need to get it repaired or replaced. I would suggest you to take quotes from few places because sometimes replacement is cheaper than repair.
If its under warranty, contact laptop manufacturer's customer support for free repair.
In anycase do not spend more than $200 in getting it repaired because it will be a better investment to buy new laptop as computer prices are at all time low.
Feel free to ask any question or concern you may have. I will be glad to help you.
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