Home > Servers > Rack and Tower Servers > Intel > White Papers > Accelerate I/O with NVMe drives on the new Dell EMC PowerEdge R650 server > Disk bandwidth
Performance isn’t just about a single number—combining multiple measures of different aspects of performance helps tell a more complete story. IOPS indicate how many storage operations a system can perform, while disk bandwidth demonstrates the volume of data a system can read or write. A server with high disk bandwidth can process more data for large data requests such as streaming video or big data applications. At all three RAID levels, the latest-generation Dell EMC PowerEdge R650 server with NVMe storage transferred more MB per second from its pre-production 3rd Gen Intel Xeon Scalable processors to its NVMe disks than the previous- generation Dell EMC PowerEdge R640 server could from its processors to its SATA and SAS storage. Figure 3 shows the disk bandwidth that each of the two servers supported running one workload at each RAID level. For all our disk bandwidth results from testing, see the science behind this report.
RAID controllers combine the physical disks of a server into logical units and manage them. They apply RAID levels that allow storage to offer data redundancy, workload performance enhancements, or both. The new Dell PERC H755N Front RAID controller in Dell EMC PowerEdge R650 servers can allow the servers to access high-performance NVMe PCIe Gen4 storage with a redundant hardware architecture where previous Dell server generations relied on software-defined RAID solutions to do so.