Dell Vostro 3660, Owner'S Manual

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Key Specifications
The table below shows the specifications comparison between DDR3 vs. DDR4:
Table 4. DDR3 vs DDR4
Feature/Option DDR3 DDR4 DDR 4 Advantages
Chip Densities 512 Mb-8 Gb 4 Gb-16 Gb Larger DIMM capacities
Data rates 800 Mb/s-2133 Mb/s 1600 Mb/s-3200 Mb/s Migration to higher speed I/O
Voltage 1.5 V 1.2 V Reduced memory power
demand
Low voltage standard Yes (DDR3L at 1.35V) Anticipated at 1.05V Memory Power Reductions
Internal banks 8 16 Higher data rates
Bank groups (BG) 0 4 Faster burst accesses
VREF inputs 2 —DQs and CMD/ADDR 1 — CMD/ADDR VREFDQ Now Internal
tCK — DLL Enabled 300 Mhz-800 Mhz 667Mhz-1.6Ghz Higher data rates
tCK — DLL Disabled 10MHz – 125MHz (optional) Undefined to 125MHz DLL-off now fully supported
Read Latency AL+CL AL+CL Expanded values
Write Latency AL+CWL AL+CWL Expanded values
DQ Driver (ALT) 40&Omega 48&Omega Optimal for PtP Applications
DQ Bus SSTL15 POD12 Less I/O Noise and Power
RTT Values (in Ω) 120,60,40,30,20 240,120,80,60,48,40,34 Support for higher data rates
RTT not allowed READ Bursts Disables during READ Bursts Ease of use
ODT Modes Nominal, Dynamic Nominal, Dynamic,Park Add’l Control Mode; OTF Value
Change
ODT Control ODT Signaling Required ODT Signaling Not Required Ease of ODT Control; Allows
Non-ODT Routing, PtP Apps
Multi-Purpose Register Four Registers – 1 Defined, 3
RFU Four Registers – 3 Defined, 1
RFU Provides Additional Specialty
Readout
DIMM Types RDIMM, LRDIMM, UDIMM,
SODIMM RDIMM, LRDIMM, UDIMM,
SODIMM
DIMM Pins 240 (R, LR, U); 204 (SODIMM) 288 (R, LR, U); 260 (SODIMM)
RAS ECC CRC, Parity, Addressability,
GDM More RAS features; improved
data integrity
DDR4 Details
There are subtle differences between DDR3 and DDR4 memory modules, as listed below.
Key notch difference
34 Technology and components