Can you help me?

[JenMacca]

Okay, I know that my monitor is really old, and it's been having problems lately, like when it's on for quite a while, the screen starts appearing shaky and wavy.... anyway......early this week it started doing something different. I tried to turn my computer on, and it beeped three times, and the monitor wouldn't come on. I flipped the power switch on and off a few times and the monitor came on, and all was well. Well, it's been happening more and more frequently since then, and has gotten worse, like it happens every time I even need to restart now. And this morning when I went to turn it on, it wouldn't come on very easily at all....I had to work at it for half an hour just to get the damn thing to work. And since then the computer's locked several times, and I've had to battle with it each time then, too. All the wires are plugged in just fine, I checked that..... but do you think the problem is with the computer or with the monitor? I'm thinking it's probably with the monitor, but before I go whining to dad to get me a new one, I'd at least like to be somewhat sure of what the problem is and what I need...