That's IMO a Windows problem. If you have a scaler-free monitor, why should Windows show smaller than max resolution (which don't work) but not larger than max (which don't work)? I couldn't find a senseful answer to that.
You basically need to fool Windows to pass the large resolution to the games. This is one way: http://forums.guru3d.com/showthread.php?t=366244
If PowerStrip is like back then, it could work as well.
I've hacked monitor files for Windows since I use Windows, having had quite a capable CRT for a long time and quite an incapable OS, so I might have a somewhat subjective opinion about MS and monitors on that matter.
i read about this method already, and my monitor refuse to handle a such signal.
it's actually a work-around because this ancient feature is not available anymore in CCC with non firepro graphics card .