GDDR5¶

General Information¶

Clocking¶

GDDR5 is generally referred to as quad data rate - the data rate is 4x the base clock for the memory system. However the reality is a little more complicated, as there are multiple physical clocks. For a 8Gbps GDDR5 setup, as an example;

Some OC tools and monitoring utilities will report different clocks. In general AMD cards will report CK (eg 2GHz on 8Gbps memory) and Nvidia cards will report WCK (eg 4GHz on 8Gbps memory).

IC Info¶

Elpida ("Micron Memory Japan")¶

NB #1: 1Gbit density Elpida GDDR5 (and GDDR3) products were outsourced to Winbond, and used Qimonda IP

NB #2: Elpida were bought by Micron in 2013 and became "Micron Memory Japan".

NB #3: When googling for datasheets add ED to the part number, eg EDW2032BABG. Part numbers are listed as they appear on the chips, without the ED prefix.

2Gbit Rev.A - W2032BABG¶

Factory bins:

• -40 - 4Gbps (1.5V)
• -50 - 5Gbps (1.5V)
• -60 - 6Gbps (1.5V)

2Gbit Rev.B - W2032BBBG¶

These chips were used on the Asus R9 290X Matrix Platinum when Asus were unable to source Samsung chips. Although they don't clock anything like as high as the Hynix alternative they run at tighter timings so the practical performance was higher, particularly given the 290X's already-huge memory bandwidth.

These chips don't like to be cold, and Asus included a memory heater on the 290X Matrix Platinum for this reason.

Factory bins:

• -40 - 4Gbps (1.5V)
• -50 - 5Gbps (1.5V)
• -60 - 6Gbps (1.6V)
• -6A - 6Gbps (1.5V)
• -70 - 7Gbps (1.6V)
• -7A - 7Gbps (1.6V)

4Gbit Rev.A - W4032BABG and W4032CABG*¶

Factory bins:

• -60 - 6Gbps (1.5V)
• -70 - 7Gbps (1.55V)

• -80 - 8Gbps (1.6V)

• -50-N (CABG) - 5Gbps (presumed) (1.35V)*

*CABG is "4Gb GDDR5 SGRAM for Networking" and the product brief is non-public

Hynix¶

NB #1: Hynix revisions go M, A, B, C etc
NB #2: Standard voltage is 1.5V, some bins use more
NB #3: Hynix speed bins don't appear to be consistent???

512Mbit Rev.M "MFR" - H5GQ5223MFR¶

Factory bins:

• N6C - 3.2Gbps
• N8C - 3.6Gbps
• T0C - 4Gbps
• T1C - 4.5Gbps

1Gbit Rev.M "MFR" - H5GQ1H24MJR and H5GQ1H24MFR¶

Factory bins:

• N6C - 3.2Gbps
• N8C - 3.6Gbps
• T0C - 4Gbps
• T1C - 4.5Gbps

1Gbit Rev.A "AFR" - H5GQ1H24AFR¶

Factory bins:

• T0C - 4Gbps
• T1C - 4.5Gbps
• T2L - 5Gbps (3.2Gbps @1.35V downbin)
• T3C - 5.5Gbps
• R0C - 6Gbps (1.6V)

1Gbit Rev.B "BFR" - H5GQ1H24BFR¶

Factory bins:

• T0 - 4Gbps
• T2 - 5Gbps
• R0 - 6Gbps

Voltages unknown - some bins may need 1.6V

2Gbit Rev.M "MFR" - H5GQ2H24MFR¶

Factory bins:

• T0C - 4Gbps
• T2C - 5Gbps (3.6Gbps @1.35V downbin)
• R0C - 6Gbps (1.6V)

2Gbit Rev.A "AFR" - H5GQ2H24AFR¶

Seen on Hynix-based 290Xs such as the MSI card. Notable for being extremely temperature sensitive, with 8Gbps seen on water but 6Gbps (OC from 5Gbps bin) a problem without active cooling.

Hynix website specs voltages up to 1.6V.

Factory bins:

• T0C - 4Gbps
• T2C - 5Gbps (4Gbps @1.35V downbin)
• R0C - 6Gbps (5Gbps @1.35V downbin)

2Gbit Rev.B "BFR" - H5GC(Q)2H24BFR (H5GQ2H24BFR?)¶

Hynix website specs voltages up to 1.55V.

Factory bins:

• T0 - 4Gbps
• T2 - 5Gbps
• R0 - 6Gbps

Voltages unknown - some bins may need 1.55V

4Gbit Rev.M "MFR" - H5GC(Q)4H24MFR (H5GQ4H24MFR?)¶

Factory bins:

• T0 - 4Gbps
• T2 - 5Gbps
• R0 - 6Gbps

downbins unknown

4Gbit Rev.A "AJR" - H5GQ4H24AJR¶

Factory bins:

• T2C - 6Gbps (5Gbps @1.35V downbin)
• R0C - 7Gbps (6Gbps @1.35V downbin)
• R4C - 8Gbps @1.55V (7Gbps @1.35V downbin)

8Gbit Rev.M "MJR" - H5GQ8H24MJR¶

Factory bins:

• T2C - 6Gbps (5Gbps @1.35V downbin)
• R0C - 7Gbps (6Gbps @1.35V downbin)
• R4C - 8Gbps @1.55V (7Gbps @1.35V downbin)

8Gbit Rev.A "AJR" - H5GC8H24AJR¶

Factory bins:

• R0C - 7Gbps (6Gbps @1.35V downbin)
• R2C - 8Gbps (7Gbps @1.35V downbin)

Micron¶

NB: Micron spec 1.5V operating voltage and 100C TJmax for all their GDDR5. According to Micron's own analysis there should be very little difference between junction and case temperatures, so 95C case temperature should be safe at stock voltage.

4Gbit Rev.B¶

Factory bins:

• D9XGP - 7Gbps

8Gbit Rev.A¶

Factory bins:

• D9TNP - 5Gbps
• D9SXC - 6Gbps
• D9SXD - 7Gbps
• D9TCB - 8Gbps

8Gbit Rev.B¶

Factory bins:

• D9VVQ - 7Gbps
• D9VVR - 8Gbps

Samsung¶

Samsung's bin codes refer to cycle time in ns, which may help to work out an undocumented code;

1Gbit Rev.E - K4G10325FE¶

Factory bins:

• HC05 - 4Gbps
• HC04 - 5Gbps

1Gbit Rev.G - K4G10325FG¶

Factory bins:

• HC05 - 4Gbps
• HC04 - 5Gbps
• HC03 - 6Gbps

2Gbit Rev.C - K4G20325FC¶

Factory bins:

?

2Gbit Rev.D - K4G20325FD¶

Factory bins:

• FC04 - 5Gbps
• FC03 - 6Gbps
• FC28 - 7Gbps

4Gbit Rev.C - K4G41325FC¶

Factory bins:

• HC04 - 5Gbps
• HC03 - 6Gbps
• HC28 - 7Gbps

4Gbit Rev.E - K4G41325FE¶

Factory bins:

• HC28 - 7Gbps
• HC25 - 8Gbps

8Gbit Rev.B - K4G80325FB¶

Seen doing 10Gbps on a Powercolor RX 580. One report of possibly degrading (10Gbps to <9Gbps) from hitting high temperatures, or may just be very temperature sensitive for stability - either way, it's recommended to keep it cool.

Factory bins:

• HC28 - 7Gbps
• HC25 - 8Gbps
• HC22 - 9Gbps

8Gbit Rev.C - K4G80325FC¶

Factory bins:

• HC25 - 8Gbps
• HC22 - (listed as 8Gbps on Samsung's site, presumably this is a typo and it's 9Gbps as with Rev.B)

Qimonda¶

NB: Qimonda went messily bankrupt in 2009, and technology and possibly engineers were acquired by Elpida

Qimonda ICs have a date code (yyww) in the top-right corner: https://i.imgur.com/9l527sW.png

512Mbit Revision A1 - IDGV51-05A1F1C¶

Factory bins:

• -36X - 3.6Gbps (removed in June 2008)
• -40X - 4Gbps
• -45X - 4.5Gbps (removed in December 2008)
• -50X - 5Gbps
• -55X - 5.5Gbps (added in December 2008)

1Gbit Revision A1 - IDGV1G-05A1F1C¶

Factory bins:

• -36X - 3.6Gbps (removed in June 2008)
• -40X - 4Gbps
• -45X - 4.5Gbps
• -50X - 5Gbps

Faster bins may have been added subsequently - these are from an October 2008 datasheet