Backward compatibility

DDR2 DIMMs are not advised to be astern accordant with DDR DIMMs. The cleft on DDR2 DIMMs is in a altered position from DDR DIMMs, and the pin body is college than DDR DIMMs in desktops. DDR2 is a 240-pin module, DDR is a 184-pin module. Notebooks accept 200-pin modules for DDR and DDR2, about the cleft on DDR modules is in a hardly altered position than that on DDR2 modules.

Higher-speedgrade DDR2 DIMMs are accordant with lower-speedgrade DDR2 DIMMs although the motherboard or CPU anamnesis ambassador will be apprenticed to the banned of the lower-performance modules.