PSU meltdown, need help recovering!

[snickers12]

Hey everyone.
I had a strong smell of burning this morning and smoke from the PSU. My PC was on. I went to turn it off and the PC turned off.
When i opend the box, the PSU smelt of 'the smell'.
I know what was wrong, as i had recently installed a new graphics card and my 300 watt PSU must have been overclocking.
So i bought a new 570 watt PSU and yet i still get no power...
Anyone got any ideas??

Thanks

[gvblake22]

I'm sorry to hear about your meltdown snickers! It is very possible that when your PSU malfunctioned it sent voltage spikes through the cables and fried the circuitry on your motherboard (and possibly other components as well. Do any of your fans spin up or any lights on the motherboard turn on with the new power supply? What video card did you buy? Do you have any extra motherboards (of your own or from a friend's computer) that you could try?

I also moved your post into it's own thread to get more personalized attention

[snickers12]

Thanks for the quick response
At first the graphics card and CPU fans both spin - but only for about 1/2 a second!! then they dont at all.. The graphics card is a Leadtek 7600GT AGP. dont have any other motherboards at the moment i could try with. i'm wondering whether it has fried my CPU or not....

[Quakindude]

First off, Welcome to HardwareLogic!

Secondly, what brand PSU did you get?

Thirdly, do you have a Multimeter? If so, test the PSU following our guide.

If you are sure the PSU isn't the issue, and cheapo PSU's can be bad right out of the box, then I would be leaning heavily towards a fried motherboard. Thing is, troubleshooting without having a lot of spare parts laying around can get expensive. You may replace your mobo only to find out that your CPU was also fried. Then, you find out your RAM was fried as well.

The best thing to do at this point is to find a friend that has a computer that can run your hardware. Swap your hardware, except for the PSU, into his computer one at a time until you know what is good or bad. If your RAM and CPU are good to go, then it's the mobo. It's been my experience that when you get an initial power surge that turns the fans then shuts off, it's either a fried mobo or CPU.

I have seen people, and myself included, end up rebuilding an older computer trying to troubleshoot components one at a time by buying different things. I had an AMD rig that i did that with and if I had just found a computer store to test my components at, or a buddies computer, I wouldn't of ended up spending almost as much to fix it as I would have to build a new computer.

Power Supplies going bad can do one of three things.

1. Burn up taking only the PSU out.
2. Burn up taking out one or two other components.
3. Burn up taking everything out with it.

The cheaper the PSU, the more likely it is to take out ancillary components. I've had all three happen to me.

[gvblake22]

What power supply did you purchase new? Please make a signature with all your system's components so we know what we are dealing with here (it is actually required).

Try testing just the power supply and see if it is working properly. Disconnect the PSU from all of the components in your system (including the motherboard), switch the unit off and unplug it from the wall. Then disconnect the data cable (PATA or SATA) of one of your optical drives and connect the power connector from the power supply to the optical drive.

Then take the main 24-pin ATX connector and look at the colored wires. You should see only one green wire on the whole thing. Now grab yourself a paperclip and bend it into a U shape. Insert one end of the paperclip into the pin of the green wire and the other end of the paperclip into the pin of a nearby black wire. This essentially "hot wires" the power supply enabling you to switch the unit on without having it connected to a motherboard. Now reconnect the power cable to the back of the PSU and wall and switch the unit on. Does the cooling fan on the power supply turn on? Can you open and close the tray of the optical drive?

[Quakindude]

Originally Posted by gvblake22

Now grab yourself a paperclip and bend it into a U shape. Insert one end of the paperclip into the pin of the green wire and the other end of the paperclip into the pin of a nearby black wire. This essentially "hot wires" the power supply enabling you to switch the unit on without having it connected to a motherboard.

If you do it this way, make sure you don't touch the paperclip with your hand or let the paperclip touch anything metal during the testing!

I use a 3" length of wire to do this with. Just strip off about 1/2" from each end, twist the exposed wires on each end tightly and then follow the directions above. Doesn't matter which black pin you use either. There are a few of them in the main plug.

[gvblake22]

Originally Posted by Quakindude

I use a 3" length of wire to do this with. Just strip off about 1/2" from each end, twist the exposed wires on each end tightly and then follow the directions above. Doesn't matter which black pin you use either. There are a few of them in the main plug.

aahh, yes, that is the better way for sure. I usually just use a paperclip because it is easy. You can touch it with your hand with no problem, but yeah, just don't touch anything else metal! Use the piece of insulated/coated wire instead of the paperclip if you can.

[snickers12]

i think its the mobo or CPU thats gone. Just wanted to know why? the psu was overworked and so blew but how could that affect the cpu or motherboard?
the

i think its the mobo or CPU thats gone. Just wanted to know why? the psu was overworked and so blew but how could that affect the cpu or motherboard?
the new psu is a Trust 5500 570 watt

oh sorry- thankx everyone for replying - REALLY appreciate it

[gvblake22]

Is this the power supply you bought? Not too sure about that company, I've never heard of them and the don't even list the voltage and amperage specifications of the unit on their website!

As for how your PSU could damage your system, I'm not exactly sure how it happened because it could happen in a million different ways. What likely happened is your power supply threw the voltage rails way out of spec and forced too much current through the wires and into the components shorting out and frying the delicate power regulator circuit chips on the components. But that is just a guess, no one can really tell you for sure how killed your components, electricity always takes the path of least resistance (which can vary in every environment and situation).

I would still test the power supply to make sure you didn't get a bum unit (just one more thing to rule out as the cause of your system still not working).

[snickers12]

great thanks. i will try using a digital multimeter to check whether my new PSU is a bum unit or not!!
So if it does work - then looks like i'm getting a new motherboard and CPU..... darn.....