Best Buy: Dell Optiplex Desktop Computer 2 GB Memory 40 GB Hard Drive GX520
Dell Optiplex GX520 Memory / RAM
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)
2GB Memory for Dell OptiPlex GX520 DDR2-800 PC2-6400 Desktop DIMM RAM (PARTS-QUICK Brand) at Amazon.com
Dell L280P-01 - 280W Power Supply for Optiplex GX520 GX620 DT 745 755
Retro Dell Optiplex GX520 Full Tower Intel 2.66Ghz 512mb ram 40GB fresh XP Pro | eBay
OFFTEK 1GB Replacement Memory RAM Upgrade for Dell OptiPlex GX520 (DDR2-4200 - Non-ECC) Desktop Memory at Amazon.com