They were working just prior to changing out the PSU. Why? Because I found out the hard way (hours later while breadboarding) my peripherals (a CD and DVD drive) were causing my PC to not boot. The fan will not spin when the computer is pulling really low power, apparently.(3) Replace EVERY cable in your computer with a cable that comes with the PSU (if available). The booklet instructions are very clear on this.(2) Do NOT fret if the fan briefly spins and then stops when you boot your PC. The only thing you need are the new motherboard cable connected to the PSU, the power cable connected to the PSU, and the tester plugged into the end of the cable that normally goes into the motherboard.

I read a review or two where they were complaining that you had to hook it up to the computer to test it. A couple of things I learned:(1) This includes a tester, which I absolutely love. Thankfully, I'm not new, though I still had a couple of problems getting it to function. Amazing! The instruction booklet was a little vague in that it did not tell you specifically which cables went into which slots.so if you're new to PC building or changing out parts, go watch a video or something. You can't even hear it turn on, it's so quiet. After hearing nothing but raving about how good Seasonic was, I went for this one. I needed another 750W PSU to replace my Corsair that was only two years old and having problems.

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