Re: I bought a used Alienware Area 51 R2 motherboard and installed it in my own computer.   You are trying to use Dell oem board in a non Area 51 R2 case.The Dell motherboard front panel 9 pin header is designed to be connected to the Dell proprietary FIO (daughter board) 9 pin front panel header (#7) using a 9 pin to 9 pin cable.   There is also a USB cable connected between Dell mobo and FIO.  The FIO then turn on Dell case alien head power button led.  The 9 pin front panel header (rainbow color) uses standard power switch pins (#6-8) but the rest of pinout is proprietary and not exactly mapped out yet. If we presume the 9 pinout is identical to industry standard (the motherboard has silkscreen suggesting that), it is probably Dell bios that controls the front panel 9 pin P LED and HDD LED on/off.  [IMAGE]  
Hi, I bought a used Alienware Area-51 R2 motherboard and installed it in my own computer case. I have a little problem that the computer power LED won't turn on when the computer is running. I know the problem has something to do with the motherboard because I already know the chassis LEDs are good. I also tried some external LEDs that I know are good - but still the LEDs won't turn on. Plugged the front power LED header to the LED P S connection on the motherboard. Positive and Negative are marked but I also tried to reverse the connection in case something was wired the wrong way. [IMAGE] Any ideas why the power LED won't turn up? I thought maybe it can actually work only in an original Alienware chassis but the front IO connection pins on the motherboard should be a universal thing (aren't they?) Thanks ahead!
Area-51 R2, motherboard power Led