Scaleway: Bare metal SSD ARM servers 11 years ago
Scaleway has done a nice job utilizing what is available now for 32-bit ARM compatible chips.
AMD, Applied Micro, and Cavium all have ARM 64-bit SOC's due out in servers in 2H2015, from a variety of OEM's. These SOC chips are designed for servers, with ECC, integrated SATA, 10Gbe, network accelerators, etc.
In the mean-time, 64-bit multi-core ARM dev boards are becoming available via www.96boards.org. Price for these is around $100 each instead of the $3K early access reference boards with the the server grade chips. Expectation is that 96boards.org will be offering boards with server grade chips in 2H2015 to further spur the SW ecosystem.