It's based on the Radeon 9200 architecture with 4 rendering pipelines, 1 vertex shader engine along with built-in RAMDAC, TMDS and TV-out controller.
The difference between the Radeon 9200 and Radeon 9250 seems to be slightly lower core-clock of the last mentioned, along with some more flexible PCB design guidelines allowing add-in-card makers to act depending on their vision of the market and needs of their customers.
ATI’s original DirectX 8.1 micro-architecture was first unveiled in 2001 with the RADEON 8500 and then adopted for various needs, including low-cost products.Source: X-bit Labs