With NVIDIA's Pascal release, the rumour mill - via bitsandchips.it - claim NVIDIA may dub an internal 'Base' & 'Premium' treatment.
The latter to feature GDDR5X - this, will be reserved for the GTX 1080. The former 'Base' would imply the use of GDDR5, reserved for the GTX 1070. The 16nm FinFET 'GP104' GPU's could feature 8GB of the aforementioned VRAM & a 256-bit Memory Bus.
Where the similarities end though is the performance numbers; the GTX 1080 could be pushing a colossal 384GB/s Bandwidth, with the GDDR5X claiming up to 12GBGbps speeds & potentially 2048 CUDA Cores. The GTX 1070 will be seeing 256GB/s Bandwidth, 8Gbps memory speeds & around 1664 CUDA Cores.
Some more detail on the Pascal equipped card specifications:
- Source: wccftech
This could mean the GTX 1080 will see up to a 45%/12.5% more Bandwidth & 59% increase in memory speeds over the current GTX 980/GTX 980Ti respectively.
Interestingly you will note that the CUDA Core count for the proposed GTX 1080 GPU is less than the current GTX 980 Ti - 2048 vs 2816. This is because clock speeds per CUDA Core are much higher than Maxwell - meaning Pascal GPU's will be much faster by comparison.
Naming conventions for the new GPU's have yet to be confirmed; We expect NVIDIA to announce the aforementioned GPU's at Computex, which takes place in Taiwan, May of this year.