Why does the screen turn off consistently?

Replaced the HD with a Samsung SSD and maxed out the RAM. Shortly after, my wife would be using it and the screen will randomly turn off. At that point, it will either:

1. Turn right back on, and prompt for a password to log back into the account.

or 2. Not turn back on, and the sleep indicator kicks in. Opening and closing the lid eventually 'wakes' it back up.

Has gotten worse, to the point it's not functional. If I lift it up from the bottom right corner, the screen wakes up and I can use it at that angle, but it may/may not 'sleep' again.

Recently, I managed to shut it down. When trying to turn it back on, it wouldn't turn on till I put a little twisting pressure on the left hand rest and top right corner of the body.

Please help! It runs amazingly well with the SSD and maxed out RAM, and don't want to invest in a new laptop for my wife. Thanks!