Green/blue dots all over my screen

[Jostijn1]

Iam really confused about my problem and I googled everything about it but I can't find the right answer, and I need someone who has had the same problem or someone who knows the right solution.
So my problem is that sometimes when I turn on my pc, I get green and blue dots in my screen like artifacts. But sometimes there is nothing when I turn my pc on. Its also weird that when I have it on my desktop and open a game, its not in the game and when I press Alt + Tab its also gone on my desktop. I have send my GPU back and got a new one but when I installed it and turned my pc on with the NEW GPU, it had the same problem AGAIN! I have uninstalled my AMD drivers and installed them again. A guy I spoke to said it was my PSU and that I had to set my Voltage higher. I did that, worked but still green dots at random moments. I just don't know what to do and I really hope someone out there knows whats wrong with my pc. Or maybe its my monitor, at least thats what a friend of mine thinks is the problem.

Here is an image, you can see the green dots everywhere: http://imgur.com/D5df8PO

My specs:
MoBo: MSI Z97 PC Mate
CPU: Intel i5 4690k @ 3,5 GHz
GPU: ASUS AMD Radeon R9 290 DirectCU II OC GDDR5 4GB
PSU: Cooler Master G650M
RAM: 16 GB (2x 8 GB)
Monitor: LG 23'' 23MP65

 

[Dogsnake]

See if you can borrow a monitor from your friend for a few hours of testing. It sounds like a monitor issue.

 

[Jostijn1]

You my hve ded or stuck pixels

are you sure? because they dissapear sometimes and then my screen is ''clean''

 

[Jostijn1]

See if you can borrow a monitor from your friend for a few hours of testing. It sounds like a monitor issue.

I can borrow my parents monitor, it has the same resolution (1920x1080)
and its connected via a DVI cable. I don't know if that matters but Iam just saying for extra information

 

[Jostijn1]

What if its really my PSU, because when I was waiting on my new GPU. I played games with MoBo graphics and never had the problem. What if its just giving to less watt to my GPU, could that be possible ?

 

[Dogsnake]

One thing at a time, swap monitors first.

 

[Jostijn1]

Well I changed my monitor with my parents' and it seems that its not a problem anymore. Although I still have to bring my monitor back where I bought it and hope that I can choose one for almost the same price with extra fund. Thank you both for helping me out, I was looking for a solution since januari.
Such a small solution for a confusing problem