Dell DR4300e Owner's Manual page 151

Figure 73. Removing the 3.5 inch (x12) SAS/SATA backplane
1. release tab (2)
3. SAS cable A1
5. backplane signal cable
7. SAS cable A0/B0
9. control panel cable
11. hard drive backplane
2. SAS cable A2
4. left ear control panel cable
6. backplane power cable (2)
8. USB cable
10. right ear control panel flex cable
12. hard drive backplane connector (12)
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