Lenovo ThinkSystem SR645 Setup Manual page 10

Table 1. Server specifications (continued)
Specification
Heat sink
Memory
Internal drives
Expansion slots
ThinkSystem SR645 Setup Guide
6
Description
• Standard heat sink
• High-performance heat sink (T-shape)
For technical rules for processors and heatsinks, see
and heat sinks" on page 96.
• Slots: 32 memory module slots
• Supported memory module type:
– TruDDR4 3200, dual-rank, 16 GB/32 GB/64 GB RDIMM
– TruDDR4 3200, dual-rank, 128 GB 3DS RDIMM
• Minimum memory:
– 16 GB using RDIMMs
– 128 GB using 3DS RDIMMs
• Maximum memory:
– 2 TB using RDIMMs
– 4 TB using 3DS RDIMMs
Note: The operating speed and total memory capacity depend on the processor
model and UEFI settings.
For a list of supported memory, see the Lenovo ServerProven Web site:
https://static.lenovo.com/us/en/serverproven/index.shtml
For technical rules for memory modules, see "Technical rules for DIMMs" on page
99.
Front:
• Up to ten 2.5-inch hot-swap SAS/SATA/U.2 drives
• Up to four 3.5-inch hot-swap SAS/SATA/NVMe drives
Inside:
• Up to two internal SATA/NVMe M.2 drives
Rear:
• Up to two 2.5-inch hot-swap SAS drives
• Up to two 7mm hot-swap SATA/NVMe drives
For technical rules for drives, see "Drive bay configurations and requirements" on
page 97.
Depending on the model, your server supports up to three PCIe slots in the rear.
• PCIe x16, low-profile
• PCIe x16/x16, low-profile + low profile
• PCIe x16/x16, low profile + full-height
For locations and technical rules for PCIe slots, see "Rear view" on page 36 and
"Technical rules for PCIe adapters" on page 101.
"Technical rules for processors
.