260 sp 192 < 4870 512MB < 4870 1GB < 260 sp 216 < 4890 1GB
That's really just in general though as depending on the game the 4870 can pull ahead of the 260 sp 216, or the 260 sp 216 can pull ahead of even the 4890 while the sp 192 will pull ahead of the 4870. It just depends on the game but in general the rankings are as I listed above