Radeon HD 3870X2 sports 1024MB of GDDR3 memory, but it’s based on two RV670 cores which also support GDDR4. We can imagine the reason for choosing GDDR3 is cost, but Radeon HD 3870X2 is the flagship. It should sport the fastest components available, which currently is GDDR4. According to Fudzilla, ATI partners are preparing cards with GDDR4, which makes perfect sense. This will bump the frequencies from the current 1800MHz to at least 2000MHz, perhaps more, and result in a higher price, but hopefully not by too much.
