AMD released an updated schedule for 65nm production, where AMD Athlon 64 FX, AMD Athlon X2 (Brisbane) and AMD Sempron (Sprata) are the only left. Single-core Athlon 64 is going to fade out soon, and therefore AMD would only provide dual core processor for mainstream and performance needs.

Without any change to its macrostructure, the first tier of 65nm product would release at RevG. However, as its BrandID has been increased from 8 bits to 16 bits, new bios is a must for recognition and function enabling. Besides, 65nm Sempron is upgraded to supports DDR2 800 instead of DDR2 667.

According to the schedule, 65nm dual-core Brisbane is planned to release its Prototype in Aug, EVT (Enginerring Verification Testing)and early DVT(Design Verification Testing) version in Nov., and starting the production in Dec. The products are firstly provided to OEM use and then the open market in 2007 Q1. 4600+ (2.4GHz/512KBx2 L2) , 4200+ (2.2GHz/512KBx2 L2) and 3800+ (2GHz/512KBx2 L2) are the first option for 65nm process, and other would follow soon. For Sempron, EVT and DVT versions have trial production in 2007 Q1, and going to release in 2007 Q2.

Besides, sources indicate that the next generation K8L interface Socket AM3 supports both DDR2 and DDR3, with Hyper-Transport updated to version 3.0, supports up to 5.2GT/s (Giga-Transfer/Second; 2.0GT/s for version 1.0). In addition, Socket AM3 processor has independent clock speed and voltage control for each of the cores and the memory controller to provide a better performance. The most important is Socket AM3 Processor is designed to support Socket AM2 Motheroard with DDR2. Yet Socket AM3 Motherboard is not compatible to Socket AM2 Processor.
source here

no need to change mobo..