Dell OptiPlex 9020 (Mid 2013) - Manual (Page 27)

System Board Layout
The following image displays the system board layout.
1. Front Bezel - Power Switch Connector
2. Memory module connectors
3. Internal speaker connector
4. Front audio connector
5. CPU fan connector
6. Processor socket
7. Password jumper
8. System fan connector
9. PCIe mini card
10. HDD/ODD power connector
11. Real time clock reset jumper
12. SATA 0 connector
13. Power supply connector
14. Front-USB connector
15. SATA 1 connector
16. Intrusion-switch connector
17. 12 V power connector
18. coin-cell battery
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