Overclock.net › Forums › Graphics Cards › AMD/ATI › GDDR5 x4 Rate?
New Posts  All Forums:Forum Nav:

GDDR5 x4 Rate?

post #1 of 2
Thread Starter 
I was wondering why GDDR2 and GDDR3 are double data rate, but GDDR5 is x4 to get the reading.
post #2 of 2
Quote:
GDDR5 (Graphics Double Data Rate, version 5) is a type of graphics card memory the standards of which were set out in the GDDR5 specification by JEDEC. GDDR5 is the successor to GDDR4 and unlike its predecessors has two parallel DQ links which provide doubled I/O throughput when compared to GDDR4. GDDR5 SGRAM is a high performance dynamic random-access memory designed for applications requiring high bandwidth. GDDR5 SGRAM uses a 8n prefetch architecture and DDR interface to achieve high performance operation and can be configured to operate in x32 mode or x16 (clamshell) mode which is detected during device initialization. The GDDR5 interface transfers two 32 bit wide data words per WCK clock cycle to/from the I/O pins. Corresponding to the 8n prefetch a single write or read access consists of a 256 bit wide, two CK clock cycle data transfer at the internal memory core and eight corresponding 32 bit wide one-half WCK clock cycle data transfers at the I/O pins.
http://en.wikipedia.org/wiki/GDDR5
In Progress...
(13 items)
 
  
CPUMotherboardGraphicsRAM
Q6600 G0 @ 3.6GHz DFI DK P35-T2RS Dark PowerColor 6870 OCZ Reaper 2 x 2 GB 
Hard DriveOSMonitorKeyboard
Too Many Windows 7 Pro x64 Samsung 2333SW Logitech G15 
PowerCaseMouseMouse Pad
PC Power & Cooling Silencer 750W Quad Antec 900 Razer Death Adder Razer Goliathus Control Edition 
  hide details  
Reply
In Progress...
(13 items)
 
  
CPUMotherboardGraphicsRAM
Q6600 G0 @ 3.6GHz DFI DK P35-T2RS Dark PowerColor 6870 OCZ Reaper 2 x 2 GB 
Hard DriveOSMonitorKeyboard
Too Many Windows 7 Pro x64 Samsung 2333SW Logitech G15 
PowerCaseMouseMouse Pad
PC Power & Cooling Silencer 750W Quad Antec 900 Razer Death Adder Razer Goliathus Control Edition 
  hide details  
Reply
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: AMD/ATI
Overclock.net › Forums › Graphics Cards › AMD/ATI › GDDR5 x4 Rate?