There are four processors in the Athlon 64 X2 family which share a number of features with each other, and with existing models of Athlon 64. Athlon 64 X2 continues to use socket 939, the fabrication process is 90nm (.09 micron) using SOI (Silicon on Insulator), the 128-bit memory controller is compatible with PC1600, PC2100, PC2700 and PC3200 DDR, although you’d be barking mad to use anything but top notch memory, and there’s one bi-directional 1GHz Hyper Transport link. This gives an effective data bandwidth of 14.4GB/sec (8GB/sec x1 HyperTransport link + 6.4GB/sec memory bandwidth). X2 has 64KB of L1 instruction and 64KB of L1 data cache, just like Athlon 64.