I am using the on-chip Intel HD Graphics 4000 of my i5-3570k on a Asrock Z77 Extreme4, and it is connected to an Acer S231HL monitor via HDMI. I have another monitor attached to the on-board DVI to give an extended desktop.
The blacks on the 23" monitor didn't look black enough to me, so I found a setting in the Intel Graphics and Media Control Panel (I think the checkbox was YCbCr, which I checked) that made the blacks very black.
The problem is this: sometimes when coming out of screen saver mode, the resolution on the 23" monitor is zoomed. So my taskbar is out of sight below the bezel, and the icons along the edges are off the edge. Also, the text and fonts appear to be scaled instead of 1:1. I tried changing resolution through the control panel, and it does change the resolution but the problem remains. So far, the only solution I have found is to uninstall the intel graphics device from the device manager and reinstall it.
I installed the latest Intel graphics driver last night, but the problem remains. I also looked through the monitor's settings and could not find anything that said scaling or zoom.
Actually, there are similarities with this thread on Intel's site.