Eh... DDR2.. XDR is far better... but oh well.... Besides.. DDR is still very good, despite its high voltage ratings. Geil recently developed a new chip design called TCCD. It allows for 1.5CAS latency on DDR400, 2.0 on DDR500, and 2.5-4-4-7 on DDR600!
4GHz... LMAO! Try... oh I don't know.... 5.8... *cough*