From "UNLEASH THE DRAGON
", AMD “Dragon” Platform Technology Performance Tuning Guide
- page 15:
The Memory controller of AMD Phenom and AMD Phenom II CPUs can be set to run in Ganged mode or in Unganged mode. Ganged mode means that there is a single 128bit wide dual-channel DRAM Controller (DCT) enabled. Unganged mode enables two 64bit wide DRAM Controllers (DCT0 and DCT1). The recommended setting in most cases is the Unganged memory mode. Ganged mode may allow slightly higher Memory performance tuning and performs well in single-threaded benchmarks.
Depending on the motherboard and BIOS, it may be required manually setting the timing parameters for each DCT (in Unganged mode) when performance tuning the memory or fine tuning the timings. Some BIOS versions apply the same timings automatically for both DCTs in an Unganged mode.