AMD Athlon XP 1500+
The slowest Athlon XP desktop model (clocked at 1333MHz and rated 1500+). It runs cooler than it's predecessor, the Athlon 'Thunderbird', it can process SSE instructions and has a higher IPC (Instructions per Clockcycle).
However, an Athlon 1400 can perform better in several situations because the little performance improvements of the Athlon XP 1500+ (1333MHz) can't make up for 66MHz .