The Inq learned that the upcoming ATI Radeon X2800 (codenamed R600) will support Quad CrossFire.
The power supply manufacturers are thrilled about four cards in a high-end machine as such a system will demand a lot of power, probably even more than 1000W.
ATI can possibly push a frame or two with its Alternate Frame Rendering architecture and make it more efficient than the split screen rendering. We will have to wait and see but it sounds like in March some records are going to get broken.