Benchmarks here are generally accurate:http://www.cpubenchmark.net/cpu_list.php
Complete specs on the model including what core it's based on (Lima):http://www.cpu-world.com/CPUs/K8/AMD-Athlon%2064%20LE-1660%20-%20ADH1660IAA4DP%20(ADH1660DPBOX).html
The core is the technology and there is no such thing as a sempron core. If you are asking if it is a sempron processor, it isn't. As you yourself said, it's an athlon 64.
If you want me to list specific models of processors that compare you're going to have to tell me what you want. Modern AMD processors? Modern intel processors? Are you looking to upgrade this CPU?