IBM Tips Power6 Processor Architecture

SAN FRANCISCO — At the International Solid-State Circuits Conference (ISSCC) here, IBM Corp. tipped its next-generation Power6 processor architecture for servers.

In various papers at the event, IBM indicated that the Power6 is a 65-nm processor that operates in excess of 4-GHz. Built around silicon-on-insulator (SOI) and other technologies, the Power6 is the follow-on processor to the company’s current Power5 architecture.

In one paper, the company described a 5.6-GHz Power6 processor with 64-Kb of Level 1 data cache. The processor is said to have an eight-way, set-associative design with a two-stage pipeline supporting two independent reads or one writes per cycle.

IBM also makes use of a 5-GHz duty-cycle correction clock distribution network for the processor. In the network, the company implements a copper distribution wire that is 3 microns wide and 1.2 microns thick.

In another paper, IBM described low-latency fixed-point and binary floating-point units for the Power6. The floating-point unit incorporates “many microarchitectures, logic, circuit, latch and integration techniques to achieve [a] 6-cyle, 13-FO4 pipeline,” according to the company’s paper.The Power6 design uses dual power supplies, a logic supply in the 0.9-to-1.2 Volt range and an SRAM power supply at about 150-mV higher.