Here's my guess.  Your intergrated video card does not support that high of a graphic resolution.  I wouldn't say your laptop is too old, but you would need to get a beefier video card to support that high of a resolution.  Your monitor will only display what your graphics chip is capable of, so either check out an actual video card like the Go! series or something similar.

Since I don't know anything about your computer besides it uses the onboard graphics card, this is all an opinion.