Review on 🔌 S-Union 240W Power Supply Unit Replacement for Dell OptiPlex 390 790 960 990 3010 9010 SFF H240AS-00 H240AS-01 H240ES-00 D240ES-00 AC240AS-00 AC240ES-00 L240AS-00 PH3C2 by Joshua Talbot

Some Dell computer models have gained a reputation for having poor quality power supplies that can fail without warning and ruin your business. This replacement can save the day, and even a person with minimal computer experience can replace a faulty one in about an hour. If you have an experienced IT specialist, it doesn't take long. Almost all of our Dell Optiplex 390 and 790 computers have had power outages, so we always keep one of these spares on hand so we don't have to go more than an hour without a car. It's cheap insurance. We haven't had a surrogate error yet - it's always the original that we retrieve from a failed computer. How do we know the problem is in the power supply? Firstly, one of our old Dells isn't working, usually an Optiplex 390 or 790. Secondly, yesterday the computer was working fine and today nothing happens when we press the power button. No fan, no light, no noise. just nothing and all the cords are firmly plugged in and the power strip or UPS it is plugged into has power. Of course, there can also be other reasons, but so far a bad power supply unit was to blame. I replaced two of them myself. I have enough computer skills to identify most of the parts, but I don't know where to put them in an empty suitcase. It's actually more about my brother and I try to get him to do it whenever I can but if the computer crashes early in the day I have to do it as he can't reach us until the evening. I don't have much experience and yet I'm kind of the best (or only) candidate for this job, here's what helps me: (Thanks to my brother for doing this dusty, sneezing job, I was still only able to see the outside .) 1. Disconnect the cable from the back of the computer. Not only is this a standard practice when you're working in a computer, but you still need to do it because the cable is plugged into the power supply and you need to unplug it. Be sure to turn everything off, and then move your computer to a well-lit area where you can work comfortably. Then, ground yourself before touching anything inside the computer (touching the screw on the switch, etc.) as static electricity can damage components. 2. Grab your phone and take a picture of everything before deleting anything. Then you will be sure that everything will go back to the way it was. This is especially true of any cables you disconnect. Most only fit one way, but it's still good to know which way as they tend to be snug and it can be hard to tell if it's misaligned or if you have it all the way back , if you can't see the outlet clearly due to the narrowness in some cases.3. Dell businesses often don't need many tools these days. There were three screws on the back of the PSU securing it to the case, but otherwise I looked for blue plastic pieces that could be removed, slid, pushed, or pulled to pull things out. Pull the cable connectors straight out and insert them straight. Some of them are fixed with a clamp. I used a long thin file to get to these clips as my fingers didn't fit. A small pair of needle-nosed pliers can help you grip the connector tightly. And of course, never pull on cables.5. Work slowly and deliberately. If something seems stuck, instead of just pulling or pushing harder, try to figure out why. If the wires are running under something, you'll probably need to move it out of the way. You usually can't just pull the wires out, and you're even less likely to be able to plug them back in. There are too many of them to attach and they might even be held by clips you can't see yet. I had to put the CD drive and hard drive aside to get to one of the cables from the power supply. Both drives were held in place with blue plastic retainers, which I found while remembering tip 5. The beauty of this is that the replacement power supply matched the original perfectly. All cables were the same length and the colors of the individual wires matched. It makes this job as easy as it gets, so hopefully you'll be back in business with a working computer soon.