Barcelona will be the host to the first supercomputer project based on Nvidia's Tegra CPU combined with its Geforce GPUs. The project is viewed as Nvidia's first attempt to siphon marketshare from the prevalent x86 architecture, dominated by Intel.
The latter already has a solution called the Many Integrated Core which is essentially 50 cores on one socket, which will be manufactured using Intel's 22nm technology and aimed squarely at the HPC market.
According to Venturebeat, the current project, called Mont Blanc, wants to improve the power efficiency of super computers by using Tegra chipsets which are normally found in tablets and other mobile devices like the Motorola XOOM.
A first iteration of the super computer will include 256 Tegra CPUs and 256 GPUs, that's 1024 ARM Cortex A9 cores possibly clocked between 1.3GHz and 1.6GHz and combined.
Venturebeat's Dean Takanashi doesn't mention whether the GPU will be Nvidia's own Tesla computing cards or GPU cores onboard the Tegra chip (there are 3 per core).
The long-term aim is to build an Exascale computer which is 10^15 flops, 50 times more powerful than the 20-Petaflop super computer built by the Oak Ridge National Laboratory.