IBM x3100 M4 4U Tower Server 2582B2A

Intel® Xeon® Quad-Core E3-1220v2 3.10GHz 8MB LGA 1155
Single socket H2 (LGA 1155) supports Intel® Xeon® E3-1200 family, Intel® 2nd Generation Core i3 & Intel® Pentium® family processors

1 x 4GB DDR3 1333 240-Pin DDR3 ECC UDIMMs (PC3 10666)
4x 240-pin DIMM sockets
Up to 32GB DDR3 ECC 1333/1066MHz UDIMMs; 2 channels
DIMM Sizes * 1GB, 2GB, 4GB, 8GB

Non HDD
Up to four 3.5″ Simple Swap SATA HDDs.

IBM ServeRAID C100 SATA Controller 
Software RAID 0, 1, 10 with ServeRAID C100 controller; hardware RAID 0, 1, 1E with ServeRAID H1110, BR10il v2, M1015, M5014 and M5015. Optional RAID 5, 50 with ServeRAID M5014. Optional upgrade to RAID 5 is available for M1015.

Four PCI Express slots:
Slot 1, PCIe 3.0 x8, full-height, half-length (PCIe 2.0 in models with processors announced September 2011 – see Table 4)
Slot 2, PCIe 3.0 x16 (x8 wired), full-height, half-length (PCIe 2.0 in models with processors announced September 2011 – see Table 4)
Slot 3, PCIe 2.0 x4, full-height, half-length
Slot 4, PCIe 2.0 x1, full-height, half-length

Microsoft Windows Server 2008 R2 and 2008, Red Hat Enterprise Linux 5 and 6, SUSE Linux Enterprise Server 10 and 11, VMware ESX 4.1