If you bought a regular clocked GeForce GTX 460 from eVGA then good news, they decided to increase the clock frequencies to be a little more competitive. eVGA slapped it all arround a marketing program called Free Performance Boost.
This program simply entails a BIOS update applying higher clocks on the GTX 460 SKUs. Here it is, the EVGA 460 FPB Update, changelist as follows:
768-P3-1360-XX - EVGA GeForce GTX 460
768-P3-1362-XX - EVGA GeForce GTX 460 SuperClocked
01G-P3-1371-XX - EVGA GeForce GTX 460 1024MB EE (External Exhaust)
01G-P3-1373-XX - EVGA GeForce GTX 460 SuperClocked 1024MB EE (External Exhaust)