Dell TW855 Poweredge 1900 Motherboard - Processors supported:Quad-Core Intel Xeon 5300 sequence processors at up to 2.66GHz - Dual-Core Intel Xeon 5100 sequence processors at up to 3.0GHz - Dual-Core Intel Xeon 5000 sequence processors at up to 3.0GH - Chipset:Intel 5000 - Memory:up to 16GB (8 FBD DIMM slots): 256MB/512MB/1GB/2GB Fully Buffered DIMMs (FBD) in matched pairs, 533MHz or 667MH - I/O slots:Six total:Two 64bit/133MHz PCI-X slots on a single PCI bus - One x8 PCI Express slot - Three x4 (x8 connector) PCI Express slot