Solved: OptiPlex 745 Small Form Factor CPU upgrade - Dell Community
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Restored Dell Optiplex 745 Small Form Factor Desktop PC with Intel Core 2 Duo Processor, 4GB Memory, 80GB Hard Drive and Windows 10 Home (Monitor Not Included) (Refurbished) - Walmart.com
Dell Optiplex 745 Ultra Small Form Factor CPU Replacement - iFixit Repair Guide