3DMark has plenty of users that overclock their GPU and CPU to the max, boosting the Median Score. Don't use that to compare your performance.
Look at a benchmark instead and compare your FPS to the Benchmarks' FPS.
My R9 290x gets 1800 points below average, since people usually overclock (+120Mhz) and overvolt (+~0.5V) it just before benchmarking, giving an inflated score.
Don't worry about bad cards, you should be instead enjoying your GPU at its fullest. The 7870 is quite good even in 2015.
-Bloc97