According to X-bit Labs there will be two versions of the Radeon 9800 SE, a new graphic card of which there were mentions in the CATALYST 3.5 release notes. Both will be cheaper than the Radeon9800 and will have less functions. One version will be a low cost which specifications will look like the Radeon 9600. The other one will be more advanced and expensive, and will possibly become the successor of the Radeon9500 because they think it will have similar possibilities to make it a full functional Radeon9800 :
The first version of the RADEON 9800 SE will be made on simplified 6-layer PCB and feature 128-bit memory bus for 128MB of DDR SDRAM. The RADEON 9800 SE graphics chip will have only four active rendering pipelines. ATI Technologies again simply disables half of the VPU’s pixel pipelines and probably end-users should have a chance to re-enable them using tweaks in drivers or simply by re-soldering some resistors on the chip.
The second version of the RADEON 9800 SE graphics card will be made on 8-layer PCB and will boast with 256-bit bus for 128MB of DDR SDRAM memory. The chip will also feature only four pipelines, however, this is not an obstacle for brave overclockers and modders, is it? After certain tweaks some lucky users will probably get a fully-functional RADEON 9800 from a lower-cost RADEON 9800 SE solution.
Core and memory clocks of the RADEON 9800 SE graphics cards are to be determined, but in general I expect speeds of the RADEON 9800 SE with 128-bit memory bus to be lower compared to its brother with 256-bit bus.
There is a downside though. The Radeon9800 SE cards are designed for OEM's, soms System Integrators and Asian markets. In Europe however ATI has signed a deal with Media Markt, which will exclusively sell the Radeon9800 SE in the retail channel. They also write that it is not very likely that there will be much Radeon9800 SE products in the US.