What am i doing wrong?

[mzzxx]

I am trying to fix a pre built computer of my fathers using a power supply from another computer. They are both the same wattage except one had sata power cables coming out and one had 4 pin. I have a sata 2 hard drive we are trying to extract files from. I ordered a cable to change 4 pin to sata but it wont work. The computer powers on and all lights and fans work perfectly UNTIL I plug in the ard drive which makes all the fans stop spinning and I can smell something burning. What is going on?

 

[HEXiT]

sounds like you killed something. most likely the hdd.

 

[terry4536]

That would suggest a short. The connector on the power supply, sata cable, or hard drive is introducing a short.