150MHz R4400 CPU Upgrade

• 150MHz R4400 CPU

• 75MHz external clock rate

• Integrated 16 KB data cache

• Integrated 16 KB instruction cache

• 1MB of high-speed secondary cache (l5ns)

• Supports up to 384 MB of memory

• Superpipelined architecture

• Uncached store buffering

• Simple end-user installable board upgrade

  
  

• Balanced integer/floating point performance

• 120+ MIPS*

• 100+SPEC89*

• 82+ SPECint92*

• 86+SPECfp92*

• 22 MFLOPS*

(*) Estimated

The R4400 CPU offers IRIS Indigo and Indigo2 system users an extremely well balanced compute engine for applications doing both integer and floating-point computation. When combined with Silicon Graphics' high performance system architecture, an R4400 upgraded Indigo system gives users industry leading application performance.

Clock Frequency

• 150 MHz internal

• 75 MHz external

  
  

Primary (on-chip)

• 16 KB Instruction

• l6 KB Data

• 1MB

  
  

• Maximum size: 384 MB

• Expansion increment: 16/32 MB

  
  

• 2 RS422 Serial

• 1 Bidirectional Parallel

• 1 Ethernet

• 1 Fast SCSI-2 (10 MB/sec) on Indigo

• 2 Fast SCSI-2 (10 MB/sec) on Indigo2

• 5 Audio connectors

• 2 GIO-32 bus slots on Indigo

• 2 GIO-64 bus slots on Indigo2

  
  

Silicon Graphics has always designed computer systems as exactly that: systems. A high performance microprocessor like the MIPS R4400 is underutilized if the surrounding system architecture is not optimized to take advantage of its compute power. IRIS Indigo systems are designed to get the most out of the R4400 CPU. IRIS Indigo systems based on the R4000 family of microprocessors implement a 64-bit CPU bus as well as Silicon Graphics high performance GIO system bus.

IRIS Indigo systems implement four Silicon Graphics designed ASICS to help optimize system performance. Two of these ASICS control the system's very high memory bandwidth (up to 400 MB/sec). This memory bandwidth coupled with one megabyte of secondary cache ensures efficient memory transactions. The remaining two ASICS control the peripheral and graphics interfaces.

The combination of the 150 MHz MIPS R4400 and Silicon Graphics high performance system architecture results in a system capable of supporting the most demanding applications.