Please help. Laptop screen lines.

[Sum_Gai]

This started a few days ago. About 3 min. after logging into Windows. Swapped out GPU with exact same model can now get 15-20 min. Lines do not appear in safe mode. I use hardware monitor and temps for GPU idle at 54°C and when gaming don't exceed 74°C, voltages don't change. Any help would be appreciated as I am out of ideas.

Specs:
Laptop - Sager NP8760
OS - Win7 Pro
Motherboard - clevo w870cu
CPU - Intel i7 740QM
GPU - Ati mobility Radeon HD5870
Ram - 8GB

What I've tried so far.
-Using a different power cable.
-Using display driver uninstaller to uninstall drivers. Installed catalyst control center and crimson edition using drivers 15.7. 1 and 16.2.1.
-Using "Who Crashed" to see if it could help. (Custom, third party)
-Using external monitor.
-Lowering resolution on monitor.

Thanks in advance.

 

[webworkings]

If the lines are not appearing in "Safe Mode" then it sounds like something on your computer (malware, etc.) is causing your problem.

Have you tried plugging in an external monitor and seeing if the same problem occurs? It should if the problem is involving any software of any kind.

 

[Sum_Gai]

Yes the same thing happens when I use an external monitor. I will try runing virus scan and malware again and see if that works. Thank you.