DDR vs DDR2
- Thread starter NickFas
- Start date
- Status
RicoDirenzo
Fully Optimized
- Messages
- 2,107
DDR2 memory chips main features are :
JEDEC standard Power Supply
VDD = VDDQ = 1.8V +/-0.1V
4 internal memory banks (512Mb)
8 internal memory banks (1Gb)
Programable CAS Latency 3,4 and 5
Programmable Additive Latency: 0,1,2,3 and 4
Write Latency = Read Latency -1
Programmable Burst Length: 4 and 8
Programable Sequential / Interleave Burst
OCD (Off-chip Driver Impedance Adjustment)
ODT (On-Die Termination)
4 bit prefetch architecture
1K page size for x4 & x8, 2K page size for x16
Data-Strobe: Bidirectional, Differential
Weak Strength Data-Output Driver Option
Auto-Refresh and Self-Refresh
Power Saving Power-Down modes
7.8µs Maximum Average Periodic Refresh Interval
Package:
60 pin FBGA for x4 & x8 components
84 pin FBGA for x16 components.
Memory Classifications
Memory Speed are offered in 400, 533 & 667Mhz
Memory Chip classification are named : DDR2-400 , DDR2-533Mhz and DDR2-667Mhz
Module DIMM Classificiation are named : PC2-3200 or 400Mhz) , PC2-4200 or 533 mhz and PC2-533 or 667Mhz
Module Bandwidth : PC2-3200 = 3.2 Gb/s , PC2-4200= 4.2 Gb/s & PC2-5300= 10.6 Gb/s
DDR2 was designed to overcome many of the problems with DDR:
Feature DDR DDR2 DDR2 Advantage
Memory Package TSOP and BGA FBGA only Higher speed and improved electrical and thermal performance
On Die Termination Memory signal terminated on motherboard In chip Terminates memory signal in every chip to improve signal and integrity
Voltage 2.5 volts 1.8 Volts Lower power consumption and heat dissipation
Memory Chip Size 128Mb - 1Gb 256Mb-4Gb* 1Gb chip -> 2GB DIMM (no chip stacking)
4Gb chip -> 8GB DIMM (no chip stacking)
Frequency 200, 266, 333, 400 Mhz 400, 533, 667 Speed above 400MHz
Module Bandwidth Up to 6.4GB/s Dual Channel Up to 10.6GB/s Highest memory performance
DDR2 versus DDR Modules
DDR2 memory modules have basically the same dimensions as the DDR modules, but have different pin configurations, therefore DDR2 DIMM will not fit in the DDR memory slot.
The number of black components on a 240-pin DIMM may vary, but they always have 120 pins on the front and 120 pins on the back.While 240-pin DDR2 DIMMs, 184-pin DDR DIMMs and 168-pin DIMMs are approximately the same size, 240-pin DIMMs and 184-pin DIMMs have only one notch within the row of pins.
The table compares the different types of modules for DDR and DDR2:
DDR2 DDR
Unbuffered DIMM 240pin 1.8V 184pin 2.5V
Registered DIMM 240pin 1.8V 184pin 2.5V
SODIMM 200pin 1.8V 200pin 2.5V
Mini Registered DIMM 244pin 1.8V —
MicroDIMM 214pin 1.8V 172pin 2.5V
Because of different voltages and pin configurations, DDR2 modules will have a different "key" or notch in their connector to prevent them from being plugged into an incompatible socket. DDR2 memory modules will only fit in systems and motherboards designed to specifically support DDR2 memory.
JEDEC standard Power Supply
VDD = VDDQ = 1.8V +/-0.1V
4 internal memory banks (512Mb)
8 internal memory banks (1Gb)
Programable CAS Latency 3,4 and 5
Programmable Additive Latency: 0,1,2,3 and 4
Write Latency = Read Latency -1
Programmable Burst Length: 4 and 8
Programable Sequential / Interleave Burst
OCD (Off-chip Driver Impedance Adjustment)
ODT (On-Die Termination)
4 bit prefetch architecture
1K page size for x4 & x8, 2K page size for x16
Data-Strobe: Bidirectional, Differential
Weak Strength Data-Output Driver Option
Auto-Refresh and Self-Refresh
Power Saving Power-Down modes
7.8µs Maximum Average Periodic Refresh Interval
Package:
60 pin FBGA for x4 & x8 components
84 pin FBGA for x16 components.
Memory Classifications
Memory Speed are offered in 400, 533 & 667Mhz
Memory Chip classification are named : DDR2-400 , DDR2-533Mhz and DDR2-667Mhz
Module DIMM Classificiation are named : PC2-3200 or 400Mhz) , PC2-4200 or 533 mhz and PC2-533 or 667Mhz
Module Bandwidth : PC2-3200 = 3.2 Gb/s , PC2-4200= 4.2 Gb/s & PC2-5300= 10.6 Gb/s
DDR2 was designed to overcome many of the problems with DDR:
Feature DDR DDR2 DDR2 Advantage
Memory Package TSOP and BGA FBGA only Higher speed and improved electrical and thermal performance
On Die Termination Memory signal terminated on motherboard In chip Terminates memory signal in every chip to improve signal and integrity
Voltage 2.5 volts 1.8 Volts Lower power consumption and heat dissipation
Memory Chip Size 128Mb - 1Gb 256Mb-4Gb* 1Gb chip -> 2GB DIMM (no chip stacking)
4Gb chip -> 8GB DIMM (no chip stacking)
Frequency 200, 266, 333, 400 Mhz 400, 533, 667 Speed above 400MHz
Module Bandwidth Up to 6.4GB/s Dual Channel Up to 10.6GB/s Highest memory performance
DDR2 versus DDR Modules
DDR2 memory modules have basically the same dimensions as the DDR modules, but have different pin configurations, therefore DDR2 DIMM will not fit in the DDR memory slot.
The number of black components on a 240-pin DIMM may vary, but they always have 120 pins on the front and 120 pins on the back.While 240-pin DDR2 DIMMs, 184-pin DDR DIMMs and 168-pin DIMMs are approximately the same size, 240-pin DIMMs and 184-pin DIMMs have only one notch within the row of pins.
The table compares the different types of modules for DDR and DDR2:
DDR2 DDR
Unbuffered DIMM 240pin 1.8V 184pin 2.5V
Registered DIMM 240pin 1.8V 184pin 2.5V
SODIMM 200pin 1.8V 200pin 2.5V
Mini Registered DIMM 244pin 1.8V —
MicroDIMM 214pin 1.8V 172pin 2.5V
Because of different voltages and pin configurations, DDR2 modules will have a different "key" or notch in their connector to prevent them from being plugged into an incompatible socket. DDR2 memory modules will only fit in systems and motherboards designed to specifically support DDR2 memory.
- Status
Similar threads
