Hi nickb123, and welcome to TSG.
1) ASUS makes many different models of motherboards and video controller cards. Please provide full model numbers of both.
2) If your motherboard has a built-in video controller and you are using a plug-in video controller card, are you making sure you are plugging the monitor into the video controller card's output?
3) If your computer used to beep when you turned it on, does it still do so? Is it a single beep or some pattern?
4) Do the keyboard status light blink when the computer is turned on?
5) When you say "my PC won't connect to my monitor" is it because the monitor displays a no video input error message?
1) ASUS makes many different models of motherboards and video controller cards. Please provide full model numbers of both.
2) If your motherboard has a built-in video controller and you are using a plug-in video controller card, are you making sure you are plugging the monitor into the video controller card's output?
3) If your computer used to beep when you turned it on, does it still do so? Is it a single beep or some pattern?
4) Do the keyboard status light blink when the computer is turned on?
5) When you say "my PC won't connect to my monitor" is it because the monitor displays a no video input error message?