AMD Tonga’s 384-bit memory bus is confirmed

After more than a year of waiting, what many thought was full-scale Tonga, or Antigua as the graphics circuit is now called. However, there were those who were surprised that the graphics card Radeon R9 380X only got a 256-bit memory bus, despite the fact that 384 bits were previously more or less confirmed housed in the circuit.

Now AMD confirms to the technology site Pcper that Tonga actually has a 384 bit wide memory bus, but that it has not been activated in its entirety on any product due to cost reasons. The information comes from AMD’s Raja Koduri, who has been head of the newly formed Radeon Technologies Group since September.

What makes the costs shine with the wider bus width is not clear, but may depend on several factors. Perhaps most likely, AMD’s partners can save on the cost of developing new circuit boards and take advantage of economies of scale, so both the Radeon R9 380 and the newcomer R9 380X use the same designer.

Knowledge of Tonga’s capacity opens up for speculation about AMD’s potential future plans, which could possibly include the launch of full-scale Tonga with a 384-bit memory bus and 3 or 6 GB of GDDR5 memory.