Illustrated guide to Cyrix’s MediaGXi technology

The merging of graphics, audio, memory control and the PCI interface onto the microprocessor itself, made Cyrix’s revolutionary MediaGX architecture a natural for use with notebook PCs, delivering easy-to-use multimedia technology at an affordable price while optimizing battery life with its low-power design. In late 1998 the MediaGXi processor was instrumental in enabling notebooks to break the sub-$1,000 price point. The processor’s suitability for deployment on a small, sparsely populated motherboard also made it an attractive option for use in the sub-A4 mini-notebook format.

Virtual System Architecture (VSA) was Cyrix’s software technology which replaced hardware functionality traditionally implemented in add-on expansion cards. VSA and the integrated features were complemented by three exclusive processor technologies that managed the multimedia and system functions of the MediaGX processor – XpressRAM, XpressGRAPHICS, and XpressAUDIO.

  • XpressRAM technology enabled the MediaGX processor to avoid the delays of data moving between the external cache and main memory. By placing the memory controller onto the chip, data lookups moved directly to SDRAM and back to the CPU, eliminating the need for external cache.
  • XpressGRAPHICS technology eliminated the need for a graphics card. In a traditional PC, graphics are processed away from the main CPU through the slower PCI bus. However, with the graphics controller and accelerator moved onto the MediaGX processor, graphics processing took place at the full megahertz speed of the CPU. XpressGRAPHICS also implemented an innovative graphics compression scheme with high-speed buffering, allowing flexibility in memory configuration without the need to add expensive video memory.
  • XpressAUDIO technology took over the operations of a separate sound card. Compatible with industry-standard sound cards, it generated all sound directly from the processor set, thereby avoiding the performance and compatibility conflicts that often occurred between audio and other components.

The MediaGX architecture represented true system-design innovation and intelligent integration. However, the lack of a Level 2 cache had an adverse effect on overall system performance, reinforcing the impression that the processor was best suited to low-end, low-cost systems.