memory technology for small form factor systems
DESCRIPTION
MEMORY TECHNOLOGY FOR SMALL FORM FACTOR SYSTEMS. Bill Gervasi Chairman, JEDEC Memory Parametrics. Market Changes. Desktop PC getting smaller and smaller Flex/ATX form factor Tiny sealed box legacy free PCs Server market shifts to 1U form factor Packing more CPUs into a smaller frame - PowerPoint PPT PresentationTRANSCRIPT
MEMORY TECHNOLOGY MEMORY TECHNOLOGY FOR SMALL FORM FOR SMALL FORM FACTOR SYSTEMSFACTOR SYSTEMS
Bill Gervasi
Chairman, JEDEC Memory Parametrics
Market ChangesMarket Changes
• Desktop PC getting smaller and smallerFlex/ATX form factorTiny sealed box legacy free PCs
• Server market shifts to 1U form factorPacking more CPUs into a smaller frameHeat dissipation a top concern
• Performance ramping higher and higher
• System (fan) noise concerns
New System DesignsNew System Designsand Form Factorsand Form Factors
Combine market segmentsCombine market segments
DIMM SO-DIMM MicroDIMM
High capacity server, “4U”, Workstation
Desktop, Notebook,
“1U”, Router, Blades
Subnotebook, PDA
64MB – 2GB per slot
64-256 MB per slot
32-256 MB per slot
It’s Time for a ChangeIt’s Time for a Change
• PC demand plateau at 128-256 MBDDR SO-DIMM clearly meets this need
• 30% of FlexATX PCB is memory sockets & traces
• 1U = 86% of server market (by unit)Trying to fit 6-8 CPUs in one 19” rack
• Increasing operating frequency harder to achieve with 5¼“ DIMM
Comparing DDR Memory Comparing DDR Memory ModulesModules
DDR ModulesDDR Modules
SO-DIMM
DIMM
NEW!MicroDIMM
SO- and Micro- DIMMsSO- and Micro- DIMMs
DDR SO-DIMM = 67.6 mm
= 50% shorter!
DDR MicroDIMM = 45.5 mm
= 66% shorter!!!
DDR DIMM = 133.3 mm
North Bridge
Copper
Slots
FlexATX FootprintFlexATX Footprint
With DIMM:
17k mm2
With SO-DIMM:
7k mm2Area saved
~ 60%
Server MarketServer Market
86%
10%
4%
Edge (86)Apps (10)Database (4)
1U form factor or blade600 MHz x86 CPU256MB – 1GB RAM
(by unit shipment; source = Intel)
1U Thin and 3U Blades1U Thin and 3U Blades
1U
3U
Vertical Socket Right Angle Socket
Operating FrequencyOperating Frequency
DIMM
4,8,9,16,18,36 chips
x4, x8, x16 devices
Unbuffered or Registered
SO-DIMM
4,5,8 chips
x8, x16 devices
Unbuffered Only
MicroDIMM
4,8 chips
x16 devices
Unbuffered Only
Which do you think will run the fastest?Which do you think will run the fastest?
Matching Requirements Matching Requirements and Implementationsand Implementations
SO-DIMM RequirementsSO-DIMM Requirements
• Low cost vertical socket neededSmallest PCB footprintEnable 4 layer motherboard
• Socket concepts in progressStaggered surface mountSingle routing layer possible!
• Right angle socket okay for blade
Concept Under AnalysisConcept Under Analysis
Discussions Under WayDiscussions Under Way
Began negotiations with the major mother board manufacturers – all are
open to evaluating the concept
Of course, no one will make the move unless
WE ALL MOVE TOGETHER
Fire StartedFire Started
• One major embedded application on the hookProduction of 250 Ku/mo beginning 1Q02Enough to kick start the program
• Task group formedConference calls to gather requirementsSocket suppliers debating implementation
& cost details
We have an opportunity to establish the We have an opportunity to establish the DDR SO-DIMM as the highest volume, DDR SO-DIMM as the highest volume,
lowest cost, highest performance lowest cost, highest performance memory module in the industry.memory module in the industry.
What about MicroDIMM?What about MicroDIMM?
• Notebooks & subnotebooks
• PDAs and Web Tablets
• High density 1U servers???
High Density 1UHigh Density 1U
Inte
rcon
nect
fa
bric
and
I/O
CPU
CPU
CPU
CPU
CPU
CPU
CPU
CPU
Mem
Mem
Mem
Mem Mem
Mem
Mem
Mem
MicroDIMM RequirementsMicroDIMM Requirements
• DDR MicroDIMM used in high density 1URight angle socket okay… 1x2” footprintOne module per CPU
• No vertical socket demand seen… yet…
Heat & NoiseHeat & Noise
Dealing w/ heat and noiseDealing w/ heat and noise
• Greatest challenge for 1U server is HEAT
• Dissipating heat takes FANS
• Fans generate MORE HEAT
Fanless Desktop PC?Fanless Desktop PC?
• What doesn’t fit?MP3 music100W per channel ampBose surround sound speaker systemPC fans with 75 dB of white noise
Power: DDR vs SDRPower: DDR vs SDR
0
0.5
1
1.5
2
Relative Watts
PC100
(3.3V)
1.2X
DDR266
(2.5V)
1.0X
PC133
(3.3V)
2.0X
Lower Voltage means
Lower Power
Power: DDR vs SDRPower: DDR vs SDR
0
0.2
0.4
0.6
0.8
1
Relative MB/s per Watt
PC100
.31X
DDR266
1.0X
PC133
.25X
Double the Bandwidth yet Lower Power
DDR Reduces PowerDDR Reduces Power
• Using DDR for main memory helps control system power
• Lower power reduces or eliminates need for fans
Bold ProjectionBold Projection
• Fanless desktop PCs for home and small office will become a significant market demand
• DDR will help enable this important market segment
Another Wild CardAnother Wild Card
• Low Power SDR1.8VNo DLL Inventive refresh options
• Some focus here, especially for cell phones… will it spread?
• Features considered for DDR family, too
Cached DRAM Power ProfileCached DRAM Power Profile
NOP ACT R-PRE R R NOP
NOP R R R R NOPLower Power
Higher Power
Command Activity
Page Miss Power Profile
Page Hit Power Profile
Command Activity
…
…
ConclusionsConclusions
• Market form factors are changing
• New designs require rethinking our past assumptions
• DDR SO-DIMM could replace the DIMM for desktop applications
• Lower power would allow us to eliminate noisy fans
Thank YouThank You