Dell Optiplex GX520 Motherboard RJ291 + Intel Pentium D 3GHz CPU + 1GB RAM H8052 - The620Guy.com
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NeweggBusiness - DELL OptiPlex GX520 Desktop PC Pentium 4 3.0GHz 2GB 160GB HDD Capacity Windows XP Professional 32-bit 3 Years Warranty for School and Colleges only (Verification Required)
Genuine Dell Motherboard For Optiplex GX520 Desktop DT Systems Dell Part Numbers: PJ479, XG312, X7841, MD573, RJ290, UG982