Overclockers the famous UK etailer got a batch of 1GB DDR4 version of Radeon HD 2900XT and it claims that the card works at 740 MHz core and 2000 MHz memory.
The funny part is that Overclockers claims that the card is "SILENT" and we highly doubt this information. The store has more than ten pieces at press time and brands the card as "OcUK ATI Radeon HD 2900 XT SILENT Heatpipe 1024MB GDDR4 VIVO TV-Out/Dual DVI (PCI-Express) - Retail". This is the first time that we heard of a 1024 MB Radeon HD based on R600 as a retail product.
The overclockers usually buy cards directly from ATI (DAAMIT) and they were known for good deals with ATI's Advanced part based in UK. The overclockers get a special price as it buys a lot of cards and people knows about them.
The sad part is that you won't get much performance of this card compared to 512 MB DDR3 version but in case you want one you can buy it here.