Processor / System Bus 2 x Socket 1366 per Nodeix-Core/ Quad-Core Intel® Xeon® X5600/ 5500 Series (95W) Quad-Core Intel® Xeon® E5600/ 5500 Series (80W) Six-Core/ Quad-Core Intel® Xeon® L5600/ 5500 Series (60W/ 40W) Six-Core/ Quad-Core/ Dual-Core QPI 4.8 /5.86 /6.4 GT/s Core Logic Intel® 5500 IOH Intel® ICH10R I/O Controller Memory Total Slots: 18 DIMMs per Node (3-channel per CPU, 9-DIMM per CPU)Capacity:Maximum up to 144GB (RDIMM) per Node; Maximum up to 48GB (UDIMM) per NodeMemory Type: DDR3 1066/1333 Reg DIMM/ Unbuffered DIMM with ECC Memory Size: 1GB 2GB 4GB 8GB * (RDIMM); 1GB 2GB 4GB (UDIMM) Expansion Slots Total Slots: 1 per NodeSlot Type: 1 * PCI-E 2.0 x16 slot(x16 link)(Low profile/Half-Length) per Node Storage SATA Controller: Intel® ICH10R: 6 SATA2 300MB/s ports Intel Matrix Storage (for Windows only) (Support software RAID 0, 1, 10 & 5) LSI® MegaRAID (for Linux/Windows) (Support software RAID 0, 1, 10) HDD Bays 12 x Hot-s