During our previous tests we found out that the 65nm Athlon 64 X2 4800+ Energy Efficient processor was significantly outperformed by its regular counterparts with equal or even lower model numbers. To understand the microarchitectural reason of this, we decided to run a low-level comparison of a regular 90nm Athlon 64 X2 5200+ CPU (Windsor) and a 65nm Athlon 64 X2 4800+ EE CPU (Brisbane) in our RightMark Memory Analyzer suite.