Fundamentals of Quantitative Design and Analysis - Computer Architecture: A Quantitative Approach - page 64

FIGURE 1.22 Manufacturing cost factors for several modern processors .
1.2 [20/20/20/20] <1.6> It costs $1 billion to build a new fabrication facility. You will be selling
a range of chips from that factory, and you need to decide how much capacity to dedicate
to each chip. Your Woods chip will be 150 mm2 and will make a profit of $20 per defect-
free chip. Your Markon chip will be 250 mm2 and will make a profit of $25 per defect-free
chip. Your fabrication facility will be identical to that for the Power5. Each wafer has a 300
mm diameter.
a. [20] <1.6> How much profit do you make on each wafer of Woods chip?
b. [20] <1.6> How much profit do you make on each wafer of Markon chip?
c. [20] <1.6> Which chip should you produce in this facility?
d. [20] <1.6> What is the profit on each new Power5 chip? If your demand is 50,000
Woods chips per month and 25,000 Markon chips per month, and your facility can
fabricate 150 wafers a month, how many wafers should you make of each chip?
1.3 [20/20] <1.6> Your colleague at AMD suggests that, since the yield is so poor, you might
make chips more cheaply if you placed an extra core on the die and only threw out chips
on which both processors had failed. We will solve this exercise by viewing the yield as a
probability of no defects occurring in a certain area given the defect rate. Calculate prob-
abilities based on each Opteron core separately (this may not be entirely accurate, since the
yield equation is based on empirical evidence rather than a mathematical calculation relat-
ing the probabilities of finding errors in different portions of the chip).
a. [20] <1.6> What is the probability that a defect will occur on no more than one of the
two processor cores?
b. [20] <1.6> If the old chip cost $20 dollars per chip, what will the cost be of the new
chip, taking into account the new area and yield?
Case Study 2: Power Consumption In Computer Systems
Concepts illustrated by this case study
■ Amdahl's Law
■ Redundancy
■ MTTF
■ Power Consumption
Power consumption in modern systems is dependent on a variety of factors, including the
chip clock frequency, efficiency, disk drive speed, disk drive utilization, and DRAM. The fol-
lowing exercises explore the impact on power that different design decisions and use scenari-
os have.