At the Consumer Electronics Show in 2011, Nvidia unveiled Project Denver, a custom CPU compatible with the ARM instruction set. This processor was destined to share die space with an Nvidia GPU and deliver enough performance for desktops and servers. We haven't heard much about Project Denver in the nearly 20 months since the initial reveal, though.
According to Bright Side of News, Project Denver will come to market in Nvidia's Tegra 5 SoC, which will also feature a GPU code-named Maxwell. Denver isn't the only Colorado-themed processor in the works, though. The same story cites "sources in the know," who say a chip called Project Boulder is scheduled to arrive in 2014. This processor will purportedly target servers specifically, and it seems likely to be based on the same microarchitecture as its mile-high counterpart. The BSN post is otherwise short on specifics but suggests that Project Boulder may employ 8-16 processor cores and interface with DDR4 memory.
While it's difficult to read too much into rumors about a product that isn't due until 2014—especially since its apparent roots lie in a chip Nvidia has been silent about for nearly two years—there is some logic to a two-pronged processor lineup. Servers face different workloads than the desktops, notebooks, and tablets that may be ripe for Denver-based Tegra chips. There are much higher margins in the server space, too.