Maybe, maybe not. It can be a problem direct on the hardware of the monitor or in it's cable, the only way to eliminate the cable possibility is testing it. Of course, if you monitor has multiple connectors, in case it only has the VGA one or just the DVI one, still worth the test, but in order to make it right, you'd need to test a different cable in the same connector, or a different cable on a different kind of connector, like VGA or DVI.
Note: When I mean VGA, I don't mean Video Graphics Adapter, I mean the connector itself.