Aurora R9, motherboard specifications?

It's a custom made motherboard for that Aurora system.

A good place to get info is Dell Aurora R9 service manual.  Alienware Aurora R9 Service Manual | Dell US

1. front-chassis fan connector (FRONT_FAN)
2. power-supply connector
3. front-panel USB cable 2 (F_USB2)
4. front-panel USB cable 1 (F_USB1)
5. SATA 6 Gbps drive connector (SATA1)
6. SATA 6 Gbps drive connector (SATA2)
7. SATA 6 Gbps drive connector (SATA3)
8. SATA 6 Gbps drive connector (SATA4)
9. solid-state drive slot (M.2 SSD)
10. coin-cell battery
11. Service mode (SERVICE MODE)
12. CMOS reset jumper (CMOS_CLR)
13. Password reset jumper (PW_CLR)

14. LED controller connector (LED_CONTROLLER)

15. front audio connector (F_AUDIO)
16. PCI-Express x8 slot (SLOT4)
17. PCI-Express x4 slot (SLOT3)
18. PCI-Express x4 slot (SLOT3)
19. PCI-Express x16 mechanical/x8 electrical slot (SLOT1)
20. wireless-card slot (M.2 WIFI)
21. processor connector (AIX_CPU)
22. top-chassis fan (TOP_FAN)
23. processor-cooling assembly pump-fan connector (PUMP_FAN)
24. processor socket (CPU1)

25. memory-module slot 3 (DDR4/XMM3)

26. memory-module slot 1 (DDR4/XMM1)

27. memory-module slot 2 (DDR4/XMM2)

28. memory-module slot 4 (DDR4/XMM4)

It's a Dell/Alienware Aurora-R9 Motherboard. See PDF Service Manual. You can also Google main-processor and chipset

Unless Dell switched recently, they were previously made by Pegatron (to Dell's specs). IIRC, they make similar boards for Dell-XPS, HP, etc.

IPCFL-SH Socket: LGA 1151 Intel

Alienware aurora R9 ..esta es la placa base.  :)