Comp

Computer Architecture

Exercise 1

Due 02. November 2010, 12:15pm

Part 1. Case Study - Chip Fabrication Cost

There are many factors involved in the price of a computer chip. New, smaller technologies give a boost in performance and a drop in required chip area. In the smaller technology, one can either keep the small area or place more hardware on the chip in order to get more functionality. In this case study, we explore how different design decisions involving fabrication technology, are, and redundancy affect the cost of chips. 1.1. Table 1 gives the relevant chip statistics that influence the cost of several current chips. In the next few exercises, you will be exploring the trade-offs involved between the AMD Opteron, a single-chip processor, and the Sun Niagara, an 8-core chip. Table 1: Manufacturing cost factors for several modern processors. α = 4. Chip Die Size Estimated defect Manufacturing Transistors (mm2 ) rate (per cm2 ) size (nm) (millions) IBM Power5 389 0.30 130 276 Sun Niagara 380 0.75 90 279 AMD Opteron 199 0.75 90 233

a) What is the yield for the AMD Opteron? b) What is the yield for the Sun Niagara processor? c) Why does the Sun Niagara have a worse yield than the AMD Opteron, even though they have the same defect rate? 1.2. You are trying to figure out whether to build a new fabrication facility for your IBM Power5 chips. It costs $1 billion to build a new fabrication facility. the benefit of the new fabrication is that you predict that you will be able to sell 3 times as many chips at 2 times the price of the old chip. The new chip will have an area of 186mm2 , with a defect rate of 0.7 defects per cm2 . Assume the waver has a diameter of 300mm. Assume it costs $500 to fabricate a wafer in either technology. You were previously selling for 40% more than their cost. a) What is the cost of the old Power5 chip? b) What is the cost of the new Power5 chip? c) What was the profit on each old Power5 chip?

Coordinator: Dipl.-Ing. Philpp Mahr...