Well, I've looked to Acer's website but my laptop's driver
there is older than my Intel HD Graphics now and when I download new drivers
from Intel, it says drivers aren't validated for my computer.
As for memory corruption, I had tried MemTest for several times but there weren't any error. I will run it before I go to bed today.
I've already uninstalled McAfee and did that solutions you give. Let's see what will happen.