Solutions to dealing with hardware problems on my Dell Inspiron N5010.

I have an old Dell Inspiron N5010 with 

• • 4 GB RAM

• • Intel core i5

• • ATI Raedon HD 5470 graphics card (1 GB)

It is about 4-5 years old, so warranty is definitely void. 
I have been running into some pertinent issues lately. Specifically,

1. Sometimes the screen does not start up when I power the laptop on-not even the DELL booting screen shows (basically the display ain't on)

2. The computer is persistently getting hot even during light use-like right now while web browsing

3. The computer suddenly switches off at times (happened about 3 times in the last month so far)

4. Its display corrupts when I run a disk defrag. Previously, there was that one time when the screen corrupted right from the boot screen and the next day, this problem just disappeared. The sceen had blue lines and corrupted blue pixels. It happened a couple of times even later but then I ignore it. I thought I should mention it here.

There are no problems on the software side because I have reinstalled the operating system several times- to no avail.

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