Learning About DDR2 Memory Technology Introduction

1
Learning About DDR2 Memory TechnologyIntroduction

• What is DDR2 Memory Technology?
• What Are the Challenges to DDR?
• How Does DDR2 Meet DDR Challenges?
• How Does DDR2 Compare to DDR?
• How Is DDR2 Being Implemented?
• How Is Intel Supporting DDR2 Memory?

2
Learning About DDR2 Memory TechnologyWhat Is
DDR2 Memory?

• SDRAM Evolution
• Synchronous Dynamic RAM (SDRAM)
• Double Data Rate RAM (DDR SDRAM)
• Double Data Rate II RAM (DDR2 SDRAM)
• Architecture
• Packaging
• Latency
• Bandwidth
• Channels

3
Learning About DDR2 Memory TechnologyWhat Are
The Challenges to DDR?

• Power and thermals
• Increasing performance requirements
• Capacity and form factor
• Examples
• Registered DDR333 starts sacrificing max capacity
• DDR400 power requirements challenging for high
  density and small form factors

Relative power to DDR266. Maximum power based
on IDD4R estimates.
4
Learning About DDR2 Memory TechnologyHow Does
DDR2 Meet DDR Challenges?

• Reduced power consumption
• Increased pre-fetch size
• On-die termination
• Posted CAS and additive latency
• Improved packaging

5
Learning About DDR2 Memory TechnologyReduced
Power Consumption

• 1.8V I/O and core voltage
• Enables smaller form factors
• Creates fewer thermal issues
• Reduced page size
• Reduces bits read per activate command
• Reduces memory power consumption

6
Learning About DDR2 Memory TechnologyIncreased
Pre-Fetch

• 100-MHz core
• 4 bit pre-fetch
• 200-MHz I/O buffers
• Double data rate signaling

7
Learning About DDR2 Memory TechnologyOn-Die
Termination

• Improved signal integrity
• Higher bandwidth capability
• Reduced BOM cost

8
Learning About DDR2 Memory TechnologyPosted CAS
and Additive Latency

• Bank activation and read command occurring in the
  same clock cycle cause a collision, resulting in
  reduced bandwidth
• Posted column address strobe (CAS) - activate and
  read commands are issued and automatically
  delayed no collision

9
Learning About DDR2 Memory TechnologyImproved
Packaging

• High-density DIMMs are generally custom solutions
  by suppliers that bridge the capacity gap
• Improved stacking technology supports higher
  memory density, enabling small and thin module
  packages

Physical stack of DDR1 TSOP
Physical stack of DDR2 FBGA
10
Learning About DDR2 Memory TechnologyHow Does
DDR2 Compare to DDR?
11
Learning About DDR2 Memory TechnologyDDR2
Advantages

• Better capacity and performance
• Higher capacity DDR2-400
• Higher bandwidth capability
• Improved thermals
• Higher frequencies and smaller form factor
• Power 50 less than DDR400, 40 less than DDR333
• Very important for blade, rack, and 1-2U
  applications
• Better board real estate utilization and board
  cost
• On-die for DDR2 vs. on-server board for DDR
  terminations

12
Learning About DDR2 Memory TechnologyHow Is DDR2
Being Implemented?

• Servers
• Severs benefit from increased DIMM capacity,
  increased bandwidth and lower thermals
• Desktops
• Graphics applications can benefit from the
  increased memory bandwidth
• Notebook Computers
• Lower thermals support smaller form factor and
  higher density
• Lower voltage requirements improve power
  efficiencies

13
Learning About DDR2 Memory TechnologyAdoption of
DDR2

• Samples from major DRAM suppliers
• Evaluating with working DDR2 test platform
• Requirements driven into the Joint Electron
  Device Engineering Council (JEDEC) component spec
• No significant changes expected
• Broad validation to increase customer choices
• All major DRAM suppliers planning DDR2 production
• Many module suppliers also planning DDR2
  production
• Actively communicating demand expectations to
  suppliers

14
Learning About DDR2 Memory TechnologyHow Is
Intel Supporting DDR2 Memory?

• Intel chipsets that support DDR2
• Enterprise
• Lindenhurst
• Twincastle
• Tumwater
• Desktop Grantsdale
• Mobile Alviso

Industry DDR Demand
100
80
60
40
20
0
Q2 05
Q1 04
Q2 04
Q3 04
Q4 04
Q1 05
Q4 05
Q3 05
Predicted DDR Demand
Potential DDR2 Upside