Techniques for supporting multiple power supply units

1. An apparatus comprising:

a motherboard; and

a switch coupled to the motherboard for controlling power supply to the motherboard from a power supply unit (“PSU”),

wherein, in response to detecting a single-rail PSU connected to the motherboard:

the switch is closed in response to a power-on signal to provide main power from the single-rail PSU to the motherboard; and

the switch is opened in response to a standby signal to cut main power from the single-rail PSU to the motherboard,

wherein, in response to detecting a dual-rail PSU connected to the motherboard, the switch is opened and bypassed such that main power to the motherboard is controlled by the dual-rail PSU via transmission of the power-on signal and the standby signal, and

wherein, in response to detecting the single-rail PSU and the dual-rail PSU connected to the motherboard concurrently, the switch is opened such that main power to the motherboard is controlled by the dual-rail PSU to prevent simultaneous operation from both the single-rail PSU and the dual-rail PSU.

2. The apparatus of claim 1 , further comprising a PSU connector that is coupled to the motherboard for interfacing with the dual-rail PSU.

3. The apparatus of claim 2 , wherein the PSU connector comprises an edge connector that is coupled to an edge of the motherboard.

4. The apparatus of claim 3 , wherein the edge connector comprises one or more electrical pins that are configured to detect a connection between the dual-rail PSU and the motherboard.

5. The apparatus of claim 4 , wherein the switch is opened in response to detecting the connection between the dual-rail PSU and the motherboard via the edge connector.

6. The apparatus of claim 3 , further comprising a power distribution board (“PDB”) coupled to the dual-rail PSU and the edge connector for facilitating power distribution from the dual-rail PSU to the motherboard and other hardware components.

7. The apparatus of claim 6 , wherein the power-on signal and the standby signal are transmitted to the dual-rail PSU via the PDB.

8. The apparatus of claim 1 , wherein the switch comprises a metal-oxide-semiconductor field-effect transistor (“MosFET”).

9. The apparatus of claim 1 , wherein the switch is closed in response to a PSON_MB_N signal from the motherboard.

10. A computing system, comprising:

a motherboard;

a power supply unit (“PSU”) operationally coupled to the motherboard; and

a switch coupled to the motherboard for controlling power supply to the motherboard from the PSU,

wherein, in response to detecting that the PSU is a single-rail PSU:

the switch is closed in response to a power-on signal to provide main power from the PSU to the motherboard; and

the switch is opened in response to a standby signal to cut main power from the PSU to the motherboard,

wherein, in response to detecting that the PSU is a dual-rail PSU, the switch is opened and bypassed such that main power to the motherboard is controlled by the PSU via transmission of the power-on signal and the standby signal, and

wherein, in response to detecting the single-rail PSU and the dual-rail PSU connected to the motherboard concurrently, the switch is opened such that main power to the motherboard is controlled by the dual-rail PSU to prevent simultaneous operation from both the single-rail PSU and the dual-rail PSU.

11. The computing system of claim 10 , further comprising a PSU connector that is coupled to the motherboard for interfacing with the dual-rail PSU, the PSU connector comprising an edge connector that is coupled to an edge of the motherboard.

12. The computing system of claim 11 , wherein the edge connector comprises one or more electrical pins that are configured to detect a connection between the dual-rail PSU and the motherboard.

13. The computing system of claim 12 , wherein the switch is opened in response to detecting the connection between the dual-rail PSU and the motherboard via the edge connector.

14. The computing system of claim 11 , further comprising a power distribution board (“PDB”) coupled to the dual-rail PSU and the edge connector for facilitating power distribution from the dual-rail PSU to the motherboard and other hardware components.

15. The computing system of claim 14 , wherein the power-on signal and the standby signal are transmitted to the dual-rail PSU via the PDB.

16. The computing system of claim 10 , wherein the switch comprises a metal-oxide semiconductor field-effect transistor (“MosFET”).

17. The computing system of claim 10 , wherein the switch is closed in response to a PSON_MB_N signal from the motherboard.

18. A method, comprising:

detecting that a power supply unit (“PSU”) is connected to a motherboard, the motherboard comprising a switch for controlling power supply to the motherboard from the PSU;

in response to detecting that the PSU is a single-rail PSU:

closing the switch in response to a power-on signal to provide main power from the PSU to the motherboard; and

opening the switch in response to a standby signal to cut main power from the PSU to the motherboard;

in response to detecting that the PSU is a dual-rail PSU, opening and bypassing the switch such that main power to the motherboard is controlled by the PSU via transmission of the power-on signal and the standby signal, and

in response to detecting the single-rail PSU and the dual-rail PSU connected to the motherboard concurrently, opening the switch such that main power to the motherboard is controlled by the dual-rail PSU to prevent simultaneous operation from both the single-rail PSU and the dual-rail PSU.