Newly built computer turns on for 5 seconds, turns off right after

hi guys, just built my first computer last night with the following parts-

VGA EVGA|01G-P3-1460-KR GTX560

even though it's the first one i've built personally, i've got some experience from helping friends and family so i know where to plug everything in, how to set my pci cards, cpu, heatsink etc., but after putting it together and firing it up the system shut down after five seconds. first thing i though was PSU but i know its fine because i tested it. i feel the mobo isn't the culprit either because my computer is actually able to start, even though for only a short time. heat sink is seated properly, fans flare as soon as it turns on. i was hoping someone might have a suggestion as to what i should do next or what the problem might be. i'm scared my cpu might be damaged, i needed to use more force to tighten the lever/holder into place for my cpu than i thought i would but i might just be paranoid. i'd appreciate any help, thanks in advanced guys.
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More about newly built computer turns seconds turns after
  1. I would be questioning if the CPU power (4 or 8 pin) is plugged in...
  2. naw i made sure i had my 8 pin connected, its definitely not that
  3. If the CPU connector is not connected it will never show any signs of life.

    Just wondering, how did you test the PSU?

    It sounds like your RAM is either bad or not pushed all the way in.

    If your CPU isn't seated correctly you may need to reseat it too. It shouldn't require tremendous amounts of force to do this. If it does it may not be lined up right.

    Also, you did use thermal paste between the processor and the heat sink, correct?

    In any event, it is too early to start ruling out things, I think. I think it could still potentially be the things your gut feeling is that is not the problem. They may really not be problematic, but I think the possibility is still there.

    - Edit - If reseating the CPU and pushing hard on the RAM to get it all the way in the slot doesn't work, try taking everything out of the case, putting it all on a wooden table, and plugging the PSU twice into the motherboard, putting in the CPU and 1 stick of RAM, and try to turn it on then by putting a small metal object across the two pins in your motherboard manual labelled PWR_BTN.
  4. thank you for the link sadams, went through it and tested my computer piece by piece.

    and thanks you for the reply raiddinnn, my 8 pin power connector for the cpu was plugged in. i tested the psu on the computer i'm sending this from, ran just fine no issues at all. ram was pushed in all the way (clicked and locked in when i pushed), and i tried reseating the cpu and heat sink to no avail. i reapplied the thermal paste, didn't overdo it, tested just the cpu and mother board plugged into the psu. it still gave me the same problem. i did test every other part individually with the cpu and mobo as well but that didn't give me any result either. again, i really appreciate the help. seems like its a cpu or mobo problem from what i tested.
  5. I hate to keep posting the same cut 'n paste ...

    Problem is unlikely to be the CPU.

    Work systematically through our standard checklist and troubleshooting thread:
    I mean work through, not just read over it. We spent a lot of time on this. It should find most of the problems.

    If no luck, continue.

    The following is an expansion of my troubleshooting tips in the breadboarding link in the "Cannot boot" thread.

    I have tested the following beep patterns on Gigabyte, eVGA, and ECS motherboards. Other BIOS' may be different, but they all use a single short beep for a successful POST.

    Breadboard - that will help isolate any kind of case problem you might have.

    Breadboard with just motherboard, CPU & HSF, case speaker, and PSU.

    Make sure you plug the CPU power cable in. The system will not boot without it.

    I always breadboard a new build. It takes only a few minutes, and you know you are putting good parts in the case once you are finished.

    You can turn on the PC by momentarily shorting the two pins that the case power switch goes to. You should hear a series of long, single beeps indicating memory problems. Silence indicates a problem with (in most likely order) the PSU, motherboard, or CPU. Remember, at this time, you do not have a graphics card installed so the load on your PSU will be reduced.

    If no beeps:
    Running fans and drives and motherboard LED's do not necessarily indicate a good PSU. In the absence of a single short beep, they also do not indicate that the system is booting.

    At this point, you can sort of check the PSU. Try to borrow a known good PSU of around 550 - 600 watts. That will power just about any system with a single GPU. If you cannot do that, use a DMM to measure the voltages. Measure between the colored wires and either chassis ground or the black wires. Yellow wires should be 12 volts. Red wires: +5 volts, orange wires: +3.3 volts, blue wire : -12 volts, violet wire (standby power supply): 5 volts always on. The green wire should also have 5 volts on it. It should go to 0 volts when you press the case power button (this is also a good way to test the power switch and the associated wiring), then back to 5 volts when you release the case power switch. Tolerances are +/- 5% except for the -12 volts which is +/- 10%.

    The gray wire is really important. It should go from 0 to +5 volts when you turn the PSU on with the case switch. CPU needs this signal to boot.

    You can turn on the PSU by completely disconnecting the PSU and using a paperclip or jumper wire to short the green wire to one of the neighboring black wires.

    A way that might be easier is to use the main power plug. Working from the back of the plug where the wires come out, use a bare paperclip to short between the green wire and one of the neighboring black wires. That will do the same thing with an installed PSU. It is also an easy way to bypass a questionable case power switch.

    This checks the PSU under no load conditions, so it is not completely reliable. But if it can not pass this, it is dead. Then repeat the checks with the PSU plugged into the computer to put a load on the PSU.

    If the system beeps:
    If it looks like the PSU is good, install a memory stick. Boot. Beep pattern should change to one long and several short beeps indicating a missing graphics card.

    Silence, long single beeps, or series of short beeps indicate a problem with the memory. If you get short beeps verify that the memory is in the appropriate motherboard slots.

    Insert the video card and connect any necessary PCIe power connectors. Boot. At this point, the system should POST successfully (a single short beep). Notice that you do not need keyboard, mouse, monitor, or drives to successfully POST.
    At this point, if the system doesn't work, it's either the video card or an inadequate PSU. Or rarely - the motherboard's PCIe interface.

    Now start connecting the rest of the devices starting with the monitor, then keyboard and mouse, then the rest of the devices, testing after each step. It's possible that you can pass the POST with a defective video card. The POST routines can only check the video interface. It cannot check the internal parts of the video card.
  6. well i am having the same problem, and after trying most of what you discusse in this post, y decided to try in a different electricity plug, and after testing for sometime came to the conclution that in the place it was connected at first didnt deliver enough energy or electricity, and thats why it only turned on for a few seconds, so my tip is to try to connect it in a different location, somewhere wich has good electricity. ex i tried in the workshop wheres theres nothing pluged so it delivered enough energy. i would try to connect the pc on a no break to see if that fixes it if you dont have no where else to try it on. so far since i switch locations ive had no problems, but ill let ya know. btw sorry for my bad grammar, im a bit rusty in my english. and im still kind of a newb on pc building but wish you luck
  7. This thread is from 2011. Please leave old threads as they are.
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