Display flickering. Not a cable or monitor problem. Details in comments. : Windows10

Just plugged and started up my computer for the first time in about about a month. Display is randomly flickering on and off. Longest it’ll stay on is about 20 seconds, which is about the longest it’ll stay off as well. Can be a where’s between that and half a second. Not a monitor or cable problem, already checked. Computer is still functional while the display is off, just can’t see anything.

Dell Alienware Alpha (500GB, Intel Core i3 4th Gen., 2.9GHz, 4GB

Edit: after about 10 minutes of the computer being on monitor went blank and displayed this.