Problem with stuttering lag when not using real fullscreen
I would normally use the "real" fullscreen option that display the game in its choose resolution, but I have recently been developing games in much smaller resolution (480*320). I have noticed if I use the "Change Resolution Mode" as I use to with this small resolution I don't get the game resized or stretched out to my full screen width and length but I get a small window with a lot of black around. I understand this is because my monitors smallest allowed resolution to display in is 800*600.
To come around this I now use the "Maximised on Bootup" and "Rezise display to fill window size". This works great in stretching out the screen to look like fullscreen no matter what resolution I am really using. However I have noticed that my games have got some occasional stuttering and lag if not using the change resolution mode. It happens at very random times and does not seem to have anything to do with what is actually happening in the game. Some times it can go a while before I see it and other times it happens a lot. The frame rate counter stays stable though, but you can see the game is stuttering or some frames are skipped. It looks choppy and then the speed returns to normal after a second or two again.
This is only happening if not using the change resolution mode. If I use the real "Change Resolution Mode" the game runs butter smooth. Any ideas what to do or what is causing this?