ATI Radeon HD 5830 Review

Architecture

The Cypress GPU is designed with out-and-out performance in mind. The HD 5870 leads the way with the fully equipped GPU architecture. The HD 5830 GPU, like the HD 5850, is a cut down version that has some disabled sections. The HD 5830 GPU, known as the Cypress LE, has 6 of the 20 SIMD engines disabled leaving a total of 14 active. Each SIMD Engine is embodied by 4 texture units and 16 stream processors, each of which has 5 stream cores or Arithmetic Logic Units (ALUs); if you prefer calling them that. This setup provides the HD 5830 GPU with 56 texture units and 1,120 stream processors.

The 256-bit memory interface is maintained even though 16 of the 32 ROP Units have been disabled. Each of the eight memory controller clusters support 4 ROPs. So to achieve this, AMD disabled 2 ROPs in each cluster. This prevented them from having to to disable any of the memory controllers themselves.

Here is a schematic diagram of the GPU architecture to help illustrate this.