dude how is ur monitor connected.is it connected thro the graphics card output.my suggestion is
1)remove the graphics card (if you have),clean the fan and slot it properly into the slot
2)remove the ram sticks one by one and then slot them in.remove them for about a minute or so and then insert them.
3)is your power supply failing?Is it able to bear the monitors power.just check it out.
i dont think your monitor is at fault.either of these three might be at fault.
cheers