Refurbished: Dell OptiPlex 780 USFF Desktop Intel Core 2 Duo E8400 3.0GHz 4GB DDR3 RAM 250 GB HD DVD-RW WiFi Bluetooth Microsoft Windows 10 Pro - Newegg.com
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OptiPlex 780 Desktop (DT) Removal Guide for the Memory, Power Supply. Coin Cell, Fan and Internal Speaker | Dell India