Horizontal lines on my NEW monitor

I purchased a new 22" monitor (Acer brand), when first started up it displayed horizontal lines across the bottom fourth of the screen from side to side, the upper portion is clear of lines and has awesome color and clarity. I took the monitor back to the store thinking it was faulty, it happened to be the last one available so I hooked it up on the store display network to troubleshoot / confirm it was indeed the monitor; NO lines why hooked up at the store so I returned home and hooked it back up, the lines were gone but reappeared after a brief period, then the lines would flicker and go away only to return after a period of time. I turned both computer and monitor off overnight and when I restarted the monitor the next day the screen was crystal clear for appx. an hour - the lines appeared again after some intermittent flickering. I am at a loss for what's causing this - my old 17" monitor is clear when I hook it up. Any thoughts and or help would be greatly appreciated.

dude you sure theres no magnet or anything that may act like a magnet close to it?? from what i read it shows the electromagnetic waves...., its exactly the same if u record a monitor while running ur gonna see those lines... be sure theres no magnet or something like that close to it!...

No magnets I'm aware of but I do have a wireless (keyboard & mouse) receiver thing close to it. I'll relocate that device and see if it helps. I was actually thinking maybe it had something to do with my video card - driver updates or something along those lines.