About Memory

Dell Precision™ T7500 Service Manual

Memory Modules

Supported Memory Configurations

Memory Subsystem

Memory Slots

Memory Population Rules

WARNING: Before working inside your computer, read the safety information that shipped with your computer. For additional safety best practices information, see the Regulatory Compliance Homepage at www.dell.com/regulatory_compliance.

Your computer uses 1066 MHz and 1333Mhz DDR3 unbuffered or registered ECC SDRAM memory. DDR3 SDRAM, or double-data- rate three synchronous dynamic random access memory, is a random access memory technology. It is a part of the SDRAM family of technologies, which is one of many DRAM (dynamic random access memory) implementations, and is an evolutionary improvement over its predecessor, DDR2 SDRAM.

The primary benefit of DDR3 SDRAM is its ability to run its I/O bus at four times the speed of the memory cells it contains, thus enabling faster bus speeds and higher peak throughputs than earlier technologies. This is achieved at the cost of higher latency. Also, the DDR3 standard allows for chip capacities of 512 megabit to 8 gigabit, effectively enabling memory modules of maximum 16 gigabyte in size.

DDR3 memory comes with a promise of a power consumption reduction of 30% compared to current commercial DDR2 modules due to DDR3’s 1.5 V supply voltage. This supply voltage works well with the 90 nm fabrication technology used for most DDR3 chips. Some manufacturers further propose to use "dual-gate" transistors to reduce leakage of current.

The main benefit of DDR3 comes from the higher bandwidth made possible by DDR3’s 8 bit deep prefetch buffer, whereas DDR2’s is 4 bits, and DDR’s is 2 bits deep.

Memory Modules

Standard	Memory		Cycle	I/O Bus		Data transfers per	Module	Peak transfer
name		clock	time		clock	second	name	rate
DDR3-1066	133	MHz	7.5 ns	533	MHz	1066 Million	PC3-8500	8533 MB/s
DDR3-1333	166	MHz	6 ns	667	MHz	1333 Million	PC3-10600	10667 MB/s

Supported Memory Configurations

		Single Processor Memory Configurations
Size	DIMM	DIMM1	DIMM2	DIMM3	DIMM4	DIMM5	DIMM6
(GB)	Ranks	DIMM1	DIMM2	DIMM3	DIMM4	DIMM5	DIMM6
3	SR	1 GB	1 GB	1 GB
4	SR	1 GB	1 GB	1 GB	1 GB
4	MR	2 GB	1 GB	1 GB	1 GB
6	SR	2 GB	2 GB	2 GB
8	MR	2 GB	2 GB	2 GB	1 GB	1 GB
12	SR	2 GB	2 GB	2 GB	2 GB	2 GB	2 GB
12	DR	4 GB	4 GB	4 GB
24	DR	4 GB	4 GB	4 GB	4 GB	4 GB	4 GB
24	DR	8 GB	8 GB	8 GB
32	MR	8 GB	8 GB	4 GB	4 GB	4 GB	4 GB
48	DR	8 GB	8 GB	8 GB	8 GB	8 GB	8 GB
96	QR	16 GB	16 GB	16 GB	16 GB	16 GB	16 GB