I use an Mac Pro as my main computer. I also have a Dell XPS 8300 that I use for work stuff. I was programming a new layer to our database software. The Oracle drivers were a little long in the tooth so I was doing a re-write. I had just finished and started the compiler in debug mode. About a minute into compile time the Dell started screaming like a rocket. I wanted to get this done so I let the task finish and when there were no errors I did the final compile, committed it to the server and shutdown. I took the side of the case off and didn't see anything wrong. I hit the start button and she sounded like a rocket with a rattle this time. I unplugged all the fans with the exception of the processor fan. Still noisy. I then used my finger to stop the CPU fan for a second. Still loud as heck. Only thing left is the power supply. Stuck a pen in the fan to stop it. Box is quiet as a mouse. I head to Best Buy and pick up a new power supply. Corsair 650w modular. Bring it home and put it in. Fire up the box and get a missing boot device error. Restart and head into bios. My SSD boot drive is not listed. I think I messed up the SSD somehow so back to Best Buy I go. I buy a new Intel 256 Gig SSD. I pop it in and get ready to do an OS install. Hit F12 to boot to USB and start the install. The only drives listed to install too are the 4 I in an external SATA enclosure. Something not right. Shutdown, remove new SSD and put old one back in. While I'm in there this time I notice a marking on the PS by the plugins for the cables. Top 2 are for SATA power and bottom 2 for peripherals. What a dummy. I had the drives hooked up to the wrong place. Move them were they should be and she fires right up and is quiet as a church mouse. The moral of this. Anyone can make a mistake. Even if you think you know it all always double check your work. In my case it cost me for an SSD drive I didn't need.