I think it means that it'd perform on par with a 3.2GHz NetBurst CPU (Pentium 4/D)
Back in the NetBurst days, this rating was used by AMD to make up for the clockspeed of Intel CPUs that dumb people would think as faster (because of their higher clocks).
its an old metric, a 3200 model amd should perform the same as a 3.2ghz intel, likewsie a 3400 should perform like a 3.4ghz intel. There are several issue with this naming convention
1) It's utter bollocks
2) AMD never official rattified it (although they never really denied it eather)
3) Its doesnt work on modern chips at all