Side-by-Side Comparison
RAM
DDR2 vs. DDR3
Comparing 2 standards across 5 specifications. 5 key differences identified.
Comparing:
DDR2
DDR3
DDR2, standardized by JEDEC in September 2003, doubled DDR's internal prefetch to 4 bits and dropped operating voltage to 1.8V. Its 240-pin DIMM introduced a new pin count, but its 200-pin SO-DIMM confusingly matches DDR1's pin count -- the two are still incompatible via a different notch position.
DDR3, standardized in 2007, kept DDR2's 240-pin DIMM count but switched from a rounded to a square notch in a different position, making the two physically incompatible despite the matching pin count. It dropped voltage to 1.5V (1.35V for the low-power DDR3L variant) and raised data rates up to DDR3-2133.
Specification Comparison Table
5 Parameters| Parameter / Spec | ||
|---|---|---|
|
JEDEC Standard
|
September 2003 | 2007 |
|
DIMM Pins
|
240 | 240 (same count as DDR2; different notch shape and position -- not compatible) |
|
SO-DIMM Pins
|
200 (same count as DDR1, different notch position -- not compatible) | 204 |
|
Nominal Operating Voltage
|
1.8 V | 1.5 (1.35V for DDR3L low-voltage variant) V |
|
Data Rate Range
|
400–1066 (DDR2-400 to DDR2-1066) MT/s | 800–2133 (DDR3-800 to DDR3-2133) MT/s |