Inspiron 3670 motherboard schematic

Dell never releases internal engineering diagram, which was a statement made again and again on this forum. 

according to the motherboard schematic, it is interesting to note that only SATA_0 port (blue) is sata3.0, the rest are all sata2.0

blue for Dell blue, the fastest port

black and white are slower ports

1. memory-module slots (2)
2. SATA 2 cable connector (SATA 2)
3. SATA 1 cable connector (SATA 1)
4. coin-cell battery
5. hard-drive power cable connector (SATA PWR)
6. SATA 3 cable connector (SATA 3)
7. SATA 0 cable connector (SATA 0)
8. hard-drive power cable connector (SATA PWR)
9. power-supply unit cable connector (ATX PWR)
10. wireless-card slot
11. service mode jumper
12. CMOS clear jumper
13. password clear jumper
14. M.2 PCIe connector
15. PCI-Express x16 slot
16. PCI-Express X1 slot
17. PCI-Express X1 slot
18. processor-power cable connector (ATX CPU)
19. processor socket