PC wont start!! Help please!

Somewher between 4 or 5 years ago my dad bought me a system off ebay and the only issue I ever had was about 2 years in my power supply crapped out on me. I quickly replaced it and everything has been fine until black friday when I decided to take advantage of neweggs deals and do some upgrades. I bought a biostar 880G+mobo, 8 gigs of g.skill sniper ram, and an athlon IIx4 to replace my Asus mobo, 4 gigs of g.skill ram and athlon 64x2. Anyways 2 weeks ago I installed The Witcher on my computer and went to go do some chores, when I came back my computer was off. I tried to start it and of course it didn't. So first instincts were my power supply died again. Well I replaced it and I still have the problem. I have got it to turn on twice since this started and sometimes the fans spin a bit and the lights come on and quickly shut back off. Also when I plug it in the lights on my case are lit up meaning that the system has power to it.

Please help! I have no idea what could be causeing this. If we cant figure it out were gonna return everything to newegg and buy new parts but i would rather not have to mess with that.

Thanks in advance for any help!

P.S: My case is a Rosewill Conqueror
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  1. Well, I had the same condition as you did: Fans spin for a fraction of a second, and shuts right back off. Sometimes, I got it to start, I have no idea how. Got a new Corsair PSU, working just fine right now. It should be a PSU problem by what I read from your description.

    How much wattage does your PSU have? It might not be enough for the components you have.
  2. Well, as long as your new PSU is working and providing enough power then you need to start troubleshooting. There are numerous guides out there.

    Your first goal is to get the motherboard to POST (making sounds or flashing LEDs depending on your board). You should first try to get it to POST without any add-in cards (like your video card).

    If it doesn't POST then start peeling off components one at a time (like unplug all your ram sticks and only use one at a time[in the proper slot] with the different sticks) and rebooting each time until you get it to POST. Of course, it may be the motherboard is beat and it might never POST again. But read some basic troubleshooting, I'm sure there's something on Tom's.

    Edit: I might add that I assumed that you had some experience working inside a computer since you swapped the PSUs a couple times - but if you aren't really comfortable then seriously read some basic computer troubleshooting guides and pay particular attention to how to prevent frying your stuff with your own static charge.
  3. yeah I am somewhat familiar with the insides of the computer. I haven't built a full computer yet but i replaced the motherboard processor and ram and I can change out psu's and rewire everything. Maybe I don't have enough power? But if I didn't have enough power it would never have worked right?
  4. Kryosthefirst said:
    yeah I am somewhat familiar with the insides of the computer. I haven't built a full computer yet but i replaced the motherboard processor and ram and I can change out psu's and rewire everything. Maybe I don't have enough power? But if I didn't have enough power it would never have worked right?

    Not necessarily - since you had a PSU problem before, what was the wattage? What's the wattage on the original replacement and what's the wattage on the new one? Did you do a graphics card upgrade too? My prior post assumed you had a PSU with enough power.
  5. All of my power supplies have been 550 watts. I have had a total of three btw. The original one that came with the system, one my sisters dad gave me to replace it when it died and this new one I bought because I thought the one my sisters dad gave me died.
  6. Does it have a graphics card? What kind? Or does it have onboard graphics? And what is the brand of the PSU?
  7. I have a nvidia geforce 9800 gt. The brand is Cooler Master.

  8. CM PSU's, particularly the older ones tend to be kind of junky. THat could very well be your problem.

    When you are asking for help, always start off with the system specifications.

    However, onward to some systematic troubleshooting techniques.

    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 not, 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. In your case, leave everything installed in the case. Just unplug everything except what is listed.

    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, LED's, or fan activity:

    Check for line power at the PSU input. Extension cords, power strips, and power cords do fail.

    If you have power and no beeps, suspect components in likely order are PSU, motherboard, and CPU.

    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: 5 volts always on. 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.
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