First off all
My name is Carlos Valente and i am game designer here in brazil
If you have acess to the files of games like ex : RO2 and Requiem
Find the textures files and resize
EX: if you find a armor image of the game, probably is in .DDS extention ( file to work optimized for Directx )
You can download de plugin to open this files in photoshop
Open the file
Select normal
and resize ex: 1024:768 to 800:600 and save
Make this to all textures
the game became more ugly but can roll in low rate PCs
Sorry for my poor English, and congratulations to the forum