Why is my monitor freezing and glitching out?

Hi,

Connect an external monitor and check what its' display is like.

If it stays stable then you could have a faulty video flex cable between the motherboard and the LCD screen, faulty or loose video cable connections at either end (motherboard or LCD screen) or a faulty LCD screen.

Holding the lid at a certain angle might indicate that it could be a problem with the video cable where it passes through the hinge area to get from the case to the lid, but it could also be the act of your handling it putting pressure on the lid (screen) that may be a factor.

When you say that it is relatively new, how new? Acer normally provides a 12 month warranty on their laptops.

If yours is not yet 12 months old, verify the purchase date on the sales receipt (or other proof of purchase document) and if the warranty period is still valid, consult the warranty statement, (usually found in the documentation that came with the laptop), as to what to do to make a claim for a warranty repair or replacement. If you cannot find the information search online for Acer warranty, as what to do when making a claim might vary from country to country