Modern displays have only one native resolution, differently sized images are resized implicitly into that one way or the other:
http://en.wikipedia.org/wiki/Lcd#Specifications
http://www.tft-lcd-monitor.co.uk/tft...solution-1.htm
Pixels are actual hardware entities. Unlike in CRT displays which can in principle use any resolution, because pixels are just the spots on a continuous screen where electrons are made land, depending on the voltages applied to them.
Different manufacturers and configurations are bitches, and most times you have to figure out by yourself how to get what you want, and if you can at all. But if you have an ATI Radeon like me, try this. In the Catalyst Control Center, switch to advanced mode, go to "digital panel" or "monitor" properties > "attributes". Select "enable GPU scaling" and "maintain aspect ratio" (not "centered timings").
http://christoph.holas.name/blog/wp-...ge_scaling.png