4GBs RAM. ○. · Configuration using only HP xw · Configuration using HP xw Slot 5 Mhz PCI-X slot must be de-rated to Mhz operation in BIOS config. XW Dual Quad Core Ghz is the only model supported. The following document for the HP xw includes additional guidelines to configure your system. (alternative slot – when Slot-5 has IEEE adapter). . Slot orders are labeled from top (starting with the monitor card) to bottom. ○.