Not turning on

The laptop component most likely to be damaged by a drop is the HDD. Unless the screen is hit by some object during the fall, it is way down the list of likely suspects.

The HDD has a maximum G-force shock rating, and it is rarely very high. If the laptop was running (or suspended/hibernating) when it was dropped, the odds the HDD is damaged DOUBLE.

The only laptop HDDs I have ever seen that can survive a drop while running are Samsungs, because most new ones have a sensor that detects zero gravity (whjat you get in a fall) and locks all moving parts before it hits. One 120gb Sam in a USB case that I have has been dropped several times, while running, and still has zero bad sectors!

Anyway, since HDDs are easy to remove, I would definitely suggest removing the HDD and trying a known good HDD before you proceed with any LCD suspicions. Even if the HDD is loaded already with somebody else's OS (rare that it will fully boot/reach desktop then) you will still get a screen and some indication that the OS is loading -until it encounters different drivers that cause a critical halt. So once you see that works, buy a new HDD and you are most likely going to be OK

May be because of Loose end connections in the Ram Slots , try to de assemble each part and assemble again

Hope this would help

Dropping a laptop, can cause quite a few serious issues. Sounds to me like the lcd is compromised, and will require a replacement. The uP swap will have little to do with it. The membrane board that supplies the LCD is fragile to the touch, so dropping the unit will make it quite suspect.

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It may be the problem related to power supply.check the cmos battery also.