New power supply - weird noises start as soon as I plug in AC power cord

[matrophy]

Hello,

I replaced my Dell power supply with an aftermarket power supply. After I installed it and plugged the AC cord in and before I pushed the power on switch, a horrendous noise came out of the PC. It sounded like the hard disk was spinning like crazy. I unplugged it and reinstalled my older power supply and my PC started up OK. Could the new power supply be no good or could this be a connection problem?

 

[ko888]

What is the brand and model number of the aftermarket power supply unit?

It is possible to receive a defective unit. The noise you're hearing is most likely from a defective power supply cooling fan.

 

[matrophy]

It is an Athena Micro PS3 Hercules and supposed to be a Dell replacement. I tried to check if it was just the fan that I heard making crazy noises so I took the new PSU and plugged it in by itself and the blue light came on but not the fan. Should the fan start in this case? I did the same thing with the old PSU and the fan didn't come on when bench testing but it did come on once I installed it in the case and reconnected all of the wires.

 

[ko888]

Have the new PSU replaced under warranty, or if you can, exchange it for a better brand.

 

[matrophy]

Best answer selected by matrophy.