Nvidia GK104 Kepler GPU May Feature 256-bit Memory Bus and 2GB VRAM

So far, Nvidia hasn’t published any official details regarding the specs of its next-generation 28nm Kepler graphics cores, but this hasn’t stopped the rumor mill from spreading all sort of info about these GPUs.

The latest such report comes from Expreview, which has found out from some unnamed sources that the upcoming GK104 core will feature a 256-bit wide memory bus, which will be connected to 2GB of video buffer.

No other specifications regarding this GPU were made available, but the whole card is expected to have a TDP of 225 Watts.

Judging by the designation used by Nvidia for this core, we expect the GK104 to come as a replacement for the graphics cards in the popular GeForce GTX 560 (GF114) and GTX 460 (GF104) product families.

Little else is known about Kepler at this point in time, but much like AMD has done with the Radeon HD 7900-series, Nvidia’s next-gen GPUs will be manufactured using TSMC's high-K metal gate (HKMG) 28nm fabrication process.

Compared to Fermi, Nvidia’s upcoming graphics core is expected to be more flexible in terms of programmability.

In the second half of 2010, Nvidia promised that Kepler, and its successor Maxwell, will include virtual memory space (allowing both the GPU and the CPU to use a unified virtual memory) and pre-emption support, as well as a series of other technologies meant to improve the GPU's ability to process data without the help of the system's processor.

According to previous Nvidia estimates, these changes, combined with the new manufacturing process, should deliver 3 to 4 times the performance per Watt of the Fermi architecture in double-precision 64-bit floating point operations.

In the consumer market, Kepler-based graphics cards will most likely carry the GeForce 600 designation.