Monitor problem

Hi,

I bought a new LCD monitor as my old CRT monitor was not working well. My new LCD monitor is giving me problems. It shows unclear (dark colored patches) pictures at times. It is not persistent. I had checked the monitor on an another PC. It showing the same problem. But I still have doubts as whether my monitor could have been affected by CPU. Is there a possibility of CPU affecting a monitor ? Or is it just the monitor prob ?
Please help.