I originally played Oblivion on the PS3. Despite its age, I thought it looked amazing on that Console. Then I was inspired to get a Gaming PC. Just so I could play Oblivion with Mods.
While playing with Mods was cool, I was disappointed with the default graphics for the PC. The lacking quality in the graphics was because the PC version came out before the PS3. So eventually I embarked on learning how to Modify the Oblivion Graphics.
I settled on a configuration that adds vibrancy, without greatly sacrificing performance. Along with emulating a little bit of the PS3 Dark shading.
Take a look at the video above. You will see that Oblivion can still look like game that holds its own in graphics.