With correct pin mapping, the board works reliably with any case and standard power supply (using a 24‑pin to Dell 8‑pin adapter for the main power, if required).
This is the safest method.
: For the HDD LED (Pins 1 & 3) and Power LED (Pins 2 & 4), the positive (+) lead must be on the lower-numbered pin (Pins 1 and 2 respectively). dell mih61r mb front panel pinout