Horizontal Lines Flashing?

On my new lenovo y50 labtop, very occasioanlly the screen would flash a very thin horizontal line whether if its just browsing, gaming, or sitting idle. I've tried reinstalling the video drivers but it didnt fix the problem.
On rare occasions my screen may flick black for a split second.
They are like https://www.youtube.com/watch?v=KtKeilqC6cw.
Its not as frequent as the ones in the video but still noticeable

zzz

Any chance can hook up an external monitor ? Want to check first if this is coming from the LCD monitor on laptop. Chances can be graphics adapter on the motherboard or other hardware failure. This an HP laptop ?

If HP can try this too

Perform a hard reset on a laptop the following steps:

Turn off the Laptop
Disconnect all external connected peripheral devices such as USB storage devices, external displays, and printers.
Unplug the AC adapter from the computer.
Remove the battery from the battery compartment.
Press and hold down the Power button for about 15 seconds to drain any residual electrical charge from the capacitors that protect the memory.
Insert the battery and plug the AC adapter back into the notebook computer, but do not connect any of the peripheral devices.
Press the Power button to turn on the computer.
If a startup menu opens, use the arrow keys to select Start Windows Normally, and then press the Enter key.

I do have an external monitor but it does not have a HDMI to connect to the laptop. And its a lenovo laptop. Thanks for the reply.

chi111111 said:

I do have an external monitor but it does not have a HDMI to connect to the laptop. And its a lenovo laptop. Thanks for the reply.

Click to expand...

YW, mean only connection on the laptop for external monitor or other monitor is only HDMI connections. Did you completely uninstall the graphics drivers then reinstall the newest version ? Laptop ever been dropped or opened ? Still able to try the reset shown for HP.

Good to list your system specs here and in the post provide make and model number of laptop.

View attachment DxDiag.txtView attachment DxDiag.txt

ITs a lenovo y50-70
model number: 20378

Well a lot read in a dxdiag not that i see an issue, but do not feel going find the solution here. This is the latest NVIDIA drivers for your Graphics adapter on this laptop NVIDIA DRIVERS GeForce Game Ready Driver WHQL
Make sure have the newest drivers installed for graphics, never said if uninstalled and reinstalled or just reinstalled these drivers.
Laptops and netbooks :: Lenovo Y Series laptops :: Y50 70 Notebook Lenovo - Lenovo Support (US)
Yes i see laptop only has an HDMI output, so you are telling me you have no other monitor to try with a HDMI input ?
Make sure all other device drivers from site are updated on the system if not already.

Need to take this step by step, as we have no way yet to know if this is the monitor without trying another first.
As this can also be graphics adapter issue, either going bad.

Try going in the Display properties in Control panel or right click screen select your graphics adapter card, try adjusting different screen resolutions. Feel might not be cause, but when you do can change what you will see also as the refresh rate in Hertz next to it.