Dell OptiPlex Small Form Factor Plus 7020 Owner's Manual page 113

Figure 69. System board overview
1. Intrusion-switch connector (INTRUSION)
2. ATX CPU power connector (ATX CPU1 and ATX CPU2)
3. Processor-fan connector (FAN CPU)
4. UDIMM slots
From the left (a>b>c>d):
DIMM 3
DIMM 1
DIMM 4
DIMM 2
5. Hard-drive data connector (SATA-1)
6. M.2 2230 solid-state drive slot (M.2 PCIe SSD-1)
7. Power-button connector (PWR SW)
8. SD-card reader slot (SD CARD)
9. M.2 WLAN slot (M.2 WLAN)
10. M.2 2280 solid-state drive slot (M.2 PCIe SSD-2)
11. Chassis-fan connector (FAN SYS)
12. System power connector (ATX SYS)
13. Internal speaker (INT SPKR)
14. Hard-drive data connector (SATA-0)
15. Optical-drive/hard-drive data connector (SATA-3)
16. SATA power connector (SATA PWR)
17. PCIe x16 slot (SLOT 2)
18. PCIe x4 slot (SLOT 1)
19. M.2 2230 solid-state drive slot (M.2 PCIe SSD-0)
20. Optional Type-C connector (TYPE-C)
21. Coin-cell battery socket (RTC)
22. Optional Video connector (VIDEO)
23. Processor socket
24. Serial PS2 module connector (KB MS, SERIAL)
Removing and installing Field Replaceable Units (FRUs) 113