Dell PowerEdge R815 Technical Manual

Also see for PowerEdge R815: Manual Update Update Portfolio guide Owner's manual

Dell PowerEdge R815 Technical Manual Manual pdf 28 page image

DellDell PowerEdge R815 Technical Guide276 Memory6.1 OverviewThe PowerEdge R815 utilizes DDR3 memory which provides a high-performance, high-speed memory interface capable of low latency response and high throughput. Theplatform supports Registered ECC DDR3 DIMMs (RDIMM) and Unbuffered DDR3 DIMMs(UDIMM).The memory interface supports memory scrubbing (sequential or redirection) andpatrol scrubbing, single-bit correction and multi-bit error detection. The failure of ax4 DRAM device results in errors to one ECC symbol and can be corrected (chipkill).The failure of a x8 DRAM device results in errors to two ECC symbols, and can bedetected but cannot be corrected. If DIMMs of different speeds are mixed, all channels will operate at the fastestcommon frequency. If online sparing is enabled, identical DIMMs must be installed in the same slotsacross each channel. The first DIMM slot in each channel is color-coded with white ejection tabs forease of installation. The DIMM sockets are placed 440 mils (11.12 mm) apart, center-to-center inorder to provide enough space for sufficient airflow to cool stacked DIMMs. The R815 memory system supports up to 32 DIMMs. Population order isidentified by the silkscreen designator and the System Information Label (SIL)located on the chassis cover.6.2 DIMMs SupportedThe interface uses 1 GB, 2 GB, 4 GB, 8 GB, and 16 GB RDIMMs and 1 GB and 2 GBUDIMMs.The memory interface supports memory demand and patrol scrubbing, single-bitcorrection and multi-bit error detection.6.3 Slots/RisersThe DDR3 memory interface consists of 4 memory channels per processor socket. Eachchannel supports up to two RDIMMs for single/dual/quad rank or two UDIMMs. Eachchannel is capable of supporting up to two DDR3 memory modules. For moreinformation, see the System Memory section in the Installing System Componentschapter of the PowerEdge R815 Hardware Owner’s Manual.6.4 SpeedEach processor has 4 DDR3 channels capable of supporting speeds up to 1333MHz.Single-, dual-, and mixed- (single and dual) rank DIMM types can support speeds up to1333MHz.Quad-rank DIMMs will be available in 2011. Quad-rank DIMMs can support speeds up to1066MHz.