Screen just goes blank.

[bossyman15]

I have a LG monitor. Recently my monitor just go blank when I do whatever. At first I thought it was problem with two displays connected (One Samsung TV and one LG monitor.) I used Win + P to blindly bring up Muilt display setting to make it work again but it still randomly go blank sometimes. I tried reinstalling display driver but it didn't fix the problem. This was on Windows 7 and I upgraded to Windows 10 today but the problem are still there!

Any idea what problem it could be?

My spec:
Intel Core i5-3470
Radeon HD 7870
8GB
550 watt PSU

 

[bossyman15]

I think I fixed it. I discovered that inside my PC is very dusty and I cleaned it. I haven't gotten blank screen ever since so I guess I'm good now.