DDR2 memory products utilize FBGA memory chips for better stability, thermal efficiency, enhanced scalability and better overclockability. Additionally, DDR2 components themselves have some micro-architectural changes from the original DDR specs, such as, Off-Chip Driver calibration (OCD), On-Die Termination (ODT) as well as larger 4-bit prefetch, additive latency, and enhanced registers.Kingston's new HyperX DDR2 PC-4300 and PC2-5400 modules should be available immediately in 256MB and 512MB modules, as well as in 512MB and 1GB dual-channel kits. The 256MB modules cost $135 and $144 and 512MB cost $198 and $211, for 533MHz and 675MHz respectively. Dual-Channel kits should cost a little less than two separate memory modules.
So far only three popular memory brands – Corsair Memory, Crucial Technology and OCZ Technology Group have unveiled 667MHz memory modules. Corsair’s and OCZ’s high-speed DDR2 are certified to operate at 667MHz with CL4 4-4-12 latency settings, Crucial’s product can work at 667MHz with CL4 4-4-10 timings.
Source: X-bit Labs