Pc turns on for a second when I press button, and then dies

[RuanRex]

Good day everyone

New member here with a problem that I have been struggling with for the last two days.

It all started when I connected my computer up after moving it to the other side of the room. It started up fine the first time and I just checked that everything was plugged in correctly and working properly.I then shut it down and came back about an hour later and pressed the power button and the pc started up and screen stayed black. So I pressed the power button again and it just kept running. I pressed the power button on the back of the PSU and it went dead. Flipped it back on and pressed the cases power button again and the screen lit up with the graphics card post. Got to the windows 7 splash screen and it went black again but pc still running. However fans start spinning faster for some reason.

So I unplugged the pc and checked seating on RAM and GPU which looked fine. Tested it again and it did the same thing. So turned pc on it side and removed RAM and GPU and unplugged all HDDs and USB devices. Turned on and now the pc turns on for a split second and dies, this happens everytime I press the power button now. I have removed the Motherboard from the case and bread boarded it as I suspected a possible short but still the same thing. I've tried one stick of RAM and GPU installed but still nothing.

Any assistance in this would be greatly appreciated
My specs are as follows:
Amd Phenom II X6 1050t stock clocks
MSI 970A-G46 AM3 motherboards
2x 4GB DDR-3 1333mhz Patriot RAM.
Coolermaster Gx750w Bronze PSU
Inno3D GeForce Gtx570 1280mb GPU
2 x 250Gb Seagate Sata 7200rpm HDDs.
Coolermaster Storm Trooper case
Coolermaster V6GT cpu Heatsink.
LG Super-Multi DVD-RW optical drive.
Windows 7 Ultimate 64-bit

Please advise if any other specs are needed

 

[ko888]

What's the model number of the PSU? Is it the RS-750-ACAA-E3 or the RS-750-ACAA-D3 or the RS-750-ACAA-B3?

Try using a better quality PSU.

 

[RuanRex]

Hi ko888.
Thanks for your quick reply. I can confirm it is the RS-750-ACAA-D3. I was under the impression that this was one of the stronger PSU's available according to the salesmen that sold it to me a few years back. Do you think this is the culprit?

 

[ko888]

Hi ko888.
Thanks for your quick reply. I can confirm it is the RS-750-ACAA-D3. I was under the impression that this was one of the stronger PSU's available according to the salesmen that sold it to me a few years back. Do you think this is the culprit?

The RS-750-ACAA-D3 made by Enhance Electronics is suppose to be better than the RS-750-ACAA-E3 that was made by Seventeam. Both of those are discontinued models. They are based on the old group regulated circuit design. DOAs and early failures were known to afflict both models. The cheap Taicon and Su’scon capacitors on the RS-750-ACAA-D3 secondary side may contribute to early failure.

The latest model is the RS-750-ACAA-B3 made by CWT. This model is based on modern DC-to-DC circuit design.

The symptoms of the PSU not latching into the On state seems to point to a PSU problem. Borrow a PSU to troubleshoot with.

 

[RuanRex]

Ok thank you very much. I understand what you are saying even with my limited electronic knowledge, I will see if I canal get my hands on a PSU from a friend or someone and let you know. Thank you for your help so far.

 

[ko888]

A high quality 550W or 650W PSU would be better than a lower quality 750W PSU.

For a system using a single GeForce GTX 570 graphics card NVIDIA specifies a minimum of a 550 Watt or greater system power supply that has a maximum combined +12 Volt continuous current rating of 38 Amps or greater and that has at least two 6-pin PCI Express supplementary power connectors. (Minimum system power requirement based on a PC configured with an Intel Core i7 3.2GHz 130 Watt TDP processor.)

Total Power Supply Wattage is NOT the crucial factor in power supply selection!!! Sufficient Total Combined Continuous Power/Current Available on the +12V Rail(s) is the most critical factor.

 

[RuanRex]

Hi ko888

I have finally managed to get hold of another PSU from a friend and I am still having the same problem. However i am noticing a high pitched scream from the motherboard somewhere as soon as I flip the power button on the back of the PSU. I don't see any bulging caps or anything strange, do you think maybe the VRMs on my motherboard have blown as I have read a few stories of this happening with others (MSI 970A-G46),or possibly just something else on the motherboard that's reached its lifespan. I have unplugged everything again and just tried to run it as if it were bread boarded. I have also taken a multimeter and tested my own power supply 12v on the GPU and CPU plugs and it reads 12v. Is there anything else you would suggest I try or should I just replace the motherboard and see if it works as no one I know runs an AMD system.

Kind regards and thank you for your patience.

 

[ko888]

What was the brand and model of the PSU that you borrowed for troubleshooting?

AMD 970 chipset motherboards have held the highest reported failure rates for the past few years mainly due to VRM circuit failure.

You wouldn't be the only customer that has experienced a high pitched coil whine from that motherboard model.

Some customers have even reported that when their MSI 970A-G46 failed it took the CPU along with it.

 

[RuanRex]

The power supply i borrowed was an Isonic 500w PSU that was definitely working. I have also run it without plugging the GPU either so I wasn't drawing any extra power from the PSU when testing. All I had plugged in was the 24pin motherboard connector and the 12v ATX CPU connector and it still just spun up and died. I also used the paper lip technique on both PSUs to start them up and they ran and showed voltage on all lines. I can ask my brother to bring his pc over to test both power supplies on. I am slightly worried that if the motherboard went that it took my CPU with it now that you have mentioned it.

On a different note, which motherboard would you recommend for a reasonable price if mine has gone. I've been eyeing these two - http://www.wootware.co.za/asus-m5a97-evo-am3-atx-amd-desktop-motherboard.html and http://www.wootware.co.za/msi-990fxa-gd65-v2-amd-990fx-sb950-socket-am3-atx-desktop-motherboard.html

 

[ko888]

MSI 990FXA-GD65