Elder Scrolls Legend: Battlespire comes to mind. it requires a pentium as well as at least 16MB of ram. then again it is a DOS game released in 1997 after it was pretty much superseded by windows95
wiki says this
"The game requires a DOS emulator in order to be run on modern operating systems. However, given that it is one of the most resource-demanding DOS games ever released commercially, as of 2009 the emulation overhead causes even relatively modern PCs to run the game sluggishly in an emulator."