GDDR5 DIMM Memory Pinout and Description, Graphics Double Data Rate Memory

GDDR5 ICs

Graphics Double Data Rate

GDDR5 Pinout and Description

Graphics Double Data Rate DIMM [GDDR-DIMM, or GDDR DIMM] is similar to the JEDEC standard for Double Date Rate SDRAMs. This page covers the GDDR ICs, which are only found on high-end Video cards used in desktop PCs. Refer to the general Memory Module page for a more complete listing of different types of modules, manufactures and descriptions.
GDDR1 uses 2.5 volt signalling, GDDR2 uses 1.8 volt signalling.
GDDR 3 runs at up to around 1.5 times the speed of GDDR 2 but consumes half the power. DDR3 SDRAM devices offer data transfer rates up to 1600 Mbps.
Module densities range from 256MByte up to 8GByte for standard JEDEC modules.

**GDDR5 PinOut and Signal Assignments**
Ball	Signal		Ball	Signal		Ball	Signal		Ball	Signal		Ball	Signal
-	MF=0	MF=1	-	MF=0	MF=1	-	MF=0	MF=1	-	MF=0	MF=1	-	MF=0	MF=1
A2	DQ1	DQ25	G3	RAS	CAS	T4	DQ26	DQ2	H11	BA0 A2	BA2 A4	E13	DQ13	DQ21
B2	DQ3	DQ27	L3	CAS	RAS	U4	DQ24	DQ0	K11	BA2 A4	BA0 A2	F13	DQ15	DQ23
C2	EDC0	EDC3	A4	DQ0	DQ24	D5	WCK01	WCK23	M11	DQ22	DQ14	M13	DQ23	DQ15
D2	DBI0	DBI3	B4	DQ2	DQ26	H5	A9 A1	A11 A6	N11	DQ20	DQ12	N13	DQ21	DQ13
E2	DQ5	DQ29	D4	WCK01	WCK23	K5	A11 A6	A9 A1	T11	DQ18	DQ10	P13	DBI2	DBI1
F2	DQ7	DQ31	E4	DQ4	DQ28	P5	WCK23	WCK01	U11	DQ16	DQ8	R13	EDC2	EDC1
M2	DQ31	DQ7	F4	DQ6	DQ30	H10	BA3 A3	BA1 A5	G12	CS	WE	T13	DQ19	DQ11
N2	DQ29	DQ5	H4	A10 A0	A8 A7	K10	BA1 A5	BA3 A3	L12	WE	CS	U13	DQ17	DQ9
P2	DBI3	DBI0	K4	A8 A7	A10 A0	A11	DQ8	DQ16	A13	DQ9	DQ17	-	-	-
R2	EDC3	EDC0	M4	DQ30	DQ6	B11	DQ10	DQ18	B13	DQ11	DQ19	-	-	-
T2	DQ27	DQ3	N4	DQ28	DQ4	E11	DQ12	DQ20	C13	EDC1	EDC2	-	-	-
U2	DQ25	DQ1	P4	WCK23	WCK01	F11	DQ14	DQ22	D13	DBI1	DBI2	-	-	-

GDDR1 Bandwidth: up to 1.2Gbytes/s with a 300MHz clock,
GDDR2 Bandwidth: up to 2.0Gbytes/s with a 500MHz clock,
GDDR3 Bandwidth: up to 9.6 Gbytes/s with a 1GHz clock.
GDDR4 which is just now starting to show up provides a bandwidth of 18GHz.
GDDR5 operates at up to 5Gbps at 1.5 volts.

GDDR5 SGRAM provides a mirror function (MF) pin to change the physical location of command, address, data and WCK pins and assist in routing devices back to back. The pins affected by this Mirror Function mode are listed below.

GDDR5 operates with two different clock types. A differential command clock (CK) to where address and command inputs are referenced, and a forwarded differential write clock (WCK) where read and write data are referenced to. Being more precise, the GDDR5 SGRAM uses two write clocks, each of them assigned to two bytes. The WCK runs at twice the CK frequency. Taking a GDDR5 with 5 Gbps data rate per pin as an example, the CK clock runs with 1.25 GHz and WCK with 2.5 GHz. The CK and WCK clocks will be aligned during the initialization and training sequence. This alignment allows read and write access with minimum latency.

Qimonda GDDR DIMM Memory Road Map

GDDR DIMM Manufacturers

GDDR memory modules are found in desk tops, and workstations.
Some companies have discontinued GDDR1 support. Example IC package types:
GDDR1; TSOP-66, GDDR2; JEDEC FBGA-84, GDDR3; JEDEC FBGA-136.

GDDR DIMM Manufacturers

DIMM Sockets; DIMM/SIMM Socket Manufacturers.


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