Help me diagnose my PC issue

I have a computer I assembled back in October of 2010 using the following items.
[li]MSI K9N6PGM2-V V.2 GeForce 6100 Socket AM2+ MB[/li][li]AMD Phenom X4 9750 2.4Ghz 2MB OEM CPU [/li][li]Crucial CT25664AA800 2GB Desktop Memory Module - PC6400, DDR2, 800MHz, DIMM [/li][li]PowerUp ATX Black Mid-Tower Case - Clear Side, 2x USB, Audio Ports, 4x 5.25" Bays, 6x 3.5" Bays, 450-Watt Power Supply [/li][li] and a hard drive, DVD drive , and a CPU fan[/li][/ul]

At least one of the above items has gone bad and I can not tell which.

Symptoms are-

System will not turn on. When I press power switch nothing happens. No lights come on, no fans move it’s completely dead. I’m assuming it’s either a bad Power Supply and I could replace it with This Antec from preventing the system from turning on or a bad CPU fan which the system is detecting and not allowing it to power on.

I don’t recall turning the system off so I’m guessing it’s either a bad power supply or the CPU fan failed. If the CPU fan failed what is the odds the CPU became damaged?

When you say “no lights, no fans” do you mean you’re observing the motherboard or is this from an outside of the case perspective? If the power supply is providing power, the fans should “jump” a bit when you switch it on from the MB, though not enough to make any noise. If there are LED lights on the MB, they should briefly light up. Do you have any spare components to test with? An old MB/CPU combo or an old power supply? Does the CPU fan move freely if you give it a spin with your finger? Have you tried disconnecting the power switch cable and shorting the power pins with a screwdriver? Any events (lightning storm, power outage/surge while you were out indicated by reset clocks) or you just tried to wake up the computer one day and it was dead?

Lots of possibilities here. Check the easy stuff first (power supply switched on and set to 120V, test power switch as above) and after that it becomes a matter of what parts you have on hand to test with and how much you do or don’t want to screw around with it or gamble on hanging new parts based on hunches.

The power supply would be my primary suspect if you’re not seeing the fans jump when you press the power switch or short the pins. PowerUp appears to be a TigerDirect house brand? Cheap power supplies are a notorious source of computer failure and worse, they can take out other expensive hardware on their way out. Consult YouTube for power supply testing techniques before buying a replacement, and keep in mind that the power supply may have taken out other components so even if you determine it to be dead, it may not be the only thing you have to replace.

Sorry for your troubles. And not to pour salt in the wounds, but cheap power supplies are the epitome of false economy. If you get a new one, get a good one. Corsair or Cooler Master would be my recommendation and a 600W or better should last through your next build. Good luck!

Before possibly wasting money, it’s worth checking the basics first.

Have you checked that the power cable hasn’t come loose? Check both ends. Have you tried another power cable? And check the back of the PSU to make sure it’s not switched off there!

^^^ check the cables. Check the power strip the power cables are plugged into.

I do have another system but I’m afraid if the power supply is dodgy it will damage it. Looking inside the case there is no movement when I hit the power button. The CPU fan does spin freely by hand. I didn’t turn it off so and sleep is disabled so it was running then stopped. I didn’t notice it’s demise until I saw my backups to it stopped working.

Power cable is not loose and PSU is switched on.

Cables are good. I tried a new power cord and other devices plugged into the strip work. I even tried changing outlets on the strip.

A properly designed supply will not damage a load (ie motherboard). However even moving a power supply is too much work. With a multimeter and one minute of labor, obtain numbers from six wires. Post those numbers. Then a next reply says (without wild speculation) what specifically is defective or suspect. Numbers can even identify disconnected wires. And say why a failure occurred.

Your power supply is powered on or off by another ‘power system’ component - a power controller. Is that defective? One minute with a multimeter and a request for instructions means a best answer in the next reply - without all that “if could be …” speculation.

If could be a power supply. It could be … or request instructions on the one minute of labor using a meter. Your only alternative is to keep replacing good parts until something works.

It’s been my (admittedly limited) experience that sometimes when power supplys go bad, they can take other components with them. I had either the motherboard or PSU go bad, and the one fried the other so both needed to be replaced.

Did you try reseating everything in your motherboard? Maybe the cable from the PSU to the mobo got knocked loose. If thats not it, and you’re getting no lights at all on your motherboard (the PSU switch on the back of the case is on right?), then I’d try the PSU from your other comp just to test. If your mobo is bad I don’t think that would hurt the PSU especially if it’s just for a few minutes. If it’s not the PSU its probably the motherboard. But I’d look at PSU first.

Almost certainly the power supply, but it could have fried your motherboard on its way out, and you won’t know till you get another one. Save yourself some $$ and get the Corsair CX430 which is <$25 After rebate right now: and in general stick with 80+ certified power supplies.

Or spend less than $10 for a meter. Ask for directions. Do one minute of labor. Then have all that answered without purchasing power supplies, motherboards, etc. Most only understand shotgunning: replacing good parts until something works. Therefore would not know that every properly designed supply does not damage the load (ie motherboard). As was true long before the IBM PC even existed.

Numbers from a meter averts so much work and spending money to replace good parts.

It might be helpful if you gave a description of this meter, and what it does. Some of us know how to take computers apart but not much else in electronics. A simple and cheap diagnostic tool that can help with computer problems? Please elaborate.

Look, you can get a meter if you want and it will tell you whether the power supply is good, true. But that a “properly designed” power supply won’t ever damage the motherboard in failure (or allow the motherboard to be damaged as well in a surge situation) is oh so false - it happens often enough that I’ve seen it personally more than once.
Edit, one potential tester:

Most have so little electrical knowledge as to not know of so many functions (required in all power supplies) that even avert motherboard damage. Any 3.5 digit multimeter works fine. These meters can cost $hundreds. Or $15 in Walmart. £7 in Maplin. Or $5 in Harbor Freight. Any 3.5 digit meter works.

Also learn that power supply testers are so useless (and expensive) as to even report defective supplies as good. Useful answers always come with numbers. That tester does not.

Disconnect nothing. Leave the computer connected to AC mains and powered off.

Power meter to its 20 VDC scale. Attach its black probe to the chassis. Find a purple wire that connects the PSU to a motherboard. Push that red probe into a nylon connector to touch the purple wire. A number about 5 appears on the meter. Post that number here to three digits.

Repeat same for the green and gray wires. Record numbers for both wires (this time) before and when pressing a front ‘power on’ button. Report those numbers and behavior of each as the power on button is pressed.

Finally, report behavior and final voltage on any one red, orange, and yellow wires as the power on button is pressed.

Post three digit numbers for each of six wires as described. Then what is defective (or suspect) AND how a computer really works is posted.

I will go to HF tomorrow and get the multi-meter. It’s something I should have anyway and I will report back the numbers.