We have got some information form a reliable source that ATI will be launching the Radeon HD 2900XTX in the end anyhow but nobody is entirely clear on the exact details.
It will most likely not be out until late July or early August, but it should be on display at Computex by at least a couple of ATI's partners from what our Taiwan spies are telling us. This is the consumer version of the XTX and will look pretty much identical to the HD 2900XT except with a different sticker and more and faster GDDR-4 RAM under the cooler, i.e. this is not the 12.4in full length cards that will be available from OEM's although both PCB length versions are floating around. The model name hasn't been set as yet and it might be called XT GDDR4 or XTX, but we'll stick with XTX for now. ATI partners have the option of ordering either the GDDR-3 XT or GDDR-4 version right now.
It will feature 1GB of GDDR memory and this means a higher memory clock, up from 1650MHz DDR for the HD 2900XT to 2020MHz DDR. The core will also be boosted, but only a laughable 10MHz from 740 to 750MHz. It seems like there will be as much point in buying the Radeon HD 2900XTX as it is to buy a GeForce 8800 Ultra. Maybe the era of the super high-end cards is finally over and we will all get decent performance from an affordable graphics card, but then again, miracles doesn't happen that easily.
ATI's 1GB GDDR-4 card will likely be priced around the same as Nvidia's GeForce 8800GTX 768MB at around $550 USD and you will probably be able to buy it in late July or sometime in August.