TechSpot

Built PC does not power up

By Skoberlink
May 12, 2008
  1. I built my first PC today but when I turn it on nothing happens. No fans, no beeps, nothing so I'll start from the beginning hopefully someone can help me out.

    Build:
    RAIDMAX SMILODON ATX-612WBP Black SECC STEEL ATX Mid Tower Computer Case 500W Power Supply - Retail

    GIGABYTE GA-P35-DS3L LGA 775 Intel P35 ATX All Solid Capacitor Intel Motherboard - Retail

    XFX PVT88PYDF4 GeForce 8800GT 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready SLI Supported Video Card - Retail

    Intel Core 2 Duo E8400 Wolfdale 3.0GHz LGA 775 65W Dual-Core Processor Model BX80570E8400 - Retail

    LITE-ON 20X DVD±R DVD Burner With 12X DVD-RAM Write Black SATA Model LH-20A1S - Retail (2)

    GIGABYTE GN-WP01GS PCI Wireless Adapter - Retail

    Seagate 120GB and 400 GB hardrives (used)

    2GB memory 2x 1GB (bought to replace bad memory on another computer but turned out to be bad memory ports don't know brand etc.)

    I built it following online instructions and using my own previous knowledge of computers. It's not my first time inside one but my first time building from scratch. Assembly went well with no real problems. I used an antistatic wrist band clipped to the case. I completed assembly and flipped the power supply switch and the lights on the keyboard flashed (this is what confuses me most). I pressed the power button on the front and nothing happens. No fans, no beeps, no lights, absolutely nothing. I checked the front panel button connections and they're correct. I stripped it down to the mobo, PSU, and CPU. Same things happened. I tried shortcircuiting the PSU ATX power plug (green wire to black wire) leaving it connected to the fans. The drives were left disconnected from when I stripped it down. Again nothing happened and of course the keyboard lights didn't flash this time. This has lead me to believe that I have a bad PSU except the flashing keyboard lights confuse me. All parts were bought from newegg.com unless otherwise stated and are still eligible for replacement. So do I have a bad PSU? or a bad mobo or cpu? I believe it's safe to say it's one of those three but which I'm not sure. My personal opinion is that the CPU is least likely to be the problem. I could return any combination of the three for replacement. What are your opinions on the problem?
     
  2. peteriskandar09

    peteriskandar09 TS Rookie Posts: 35

    I use to have a similar problem it might be the connectors for the power button reset button hdd led power led are not in the right pins you have to consult your motherboard manuel and check the proper pin located for each part.
     
  3. Skoberlink

    Skoberlink TS Rookie Topic Starter

    I double checked them in my motherboard manual so they're correct. I also double checked polarity in my case manual unfortunately it was very vague and referred to colors for HDD LED and RESET SW that were wrong. For Reset: it said blue is + and white is -. The real colors were green and white so that wasn't so bad. The HDD LED was red is + and white was - but the real colors were purple and black. I believe I ahve them correct but that may be wrong. the placements for each one on the mobo is definitely correct unless the manual is wrong although all pin numbers and color codings matched something in the manual. I've checked them multiple times. I appreciate the help though.
     
  4. mailpup

    mailpup TS Special Forces Posts: 8,484   +233

    If you are using the PSU that came with the case, that would be high on my suspect list.
     
  5. Skoberlink

    Skoberlink TS Rookie Topic Starter

    Yes I am and it is at the top of my list right now. The thing that's making me question it is the flashing keyboard lights. They flash when the switch on the power supply is flipped.

    EDIT: I was not aware that a PSU that comes with a case is a problem frequently enough that it's a reason to suspect it. Should I return this and get a case and PSU seperately? I can still do that I believe... I did a lot of research and had the build checked by various people (mostly through online question and answer forums) and thought I had a pretty good one for the cost.
     
  6. Predict

    Predict TS Rookie Posts: 37

    You said the lights flashed but they didnt stay on?? If they just flashed be sure that you pluged in the wires in the correct spots. Like the power and reset wires. Also the cpu overheating would cause it to reset so heatsink must be on. Also ur psu wouldnt cause this also unless it fried something. Just make sure every thing is pluged in correct. Sometimes there are multi spots to plug in power to ur mobo ive seen some mobo that have about 3 power outlets.
     
  7. Skoberlink

    Skoberlink TS Rookie Topic Starter

    yep it has a heat sink on it as well as a fan which (like the others) isn't turning on. I've been over the diagrams several times so i'm positive everything's plugged in correctly. maybe I messed up the mobo. alright I'll return the mobo. should i go ahead and return the case/psu as well just to be sure?
     
  8. mailpup

    mailpup TS Special Forces Posts: 8,484   +233

    Power supplies can fail even though they continue to provide some power. It is not necessarily an all or nothing proposition. They can also fail to provide stable voltages or provide too low or high voltages.

    You could return the case and power supply if you want or you could discard the PSU and just buy a good quality one. While I try to buy cases without power supplies so I can get my own, I have bought a case that I wanted and discarded the questionable power supply right off the bat. There is no rule saying you must use it. PSUs that come with cases tend to be low quality units although not always. But in any case, if yours is bad, it would be simplest to replace it and keep the case.
     
  9. Tmagic650

    Tmagic650 TS Ambassador Posts: 20,987   +168

    The reset switch and the power switch wires do not have polarity requirements. Only the hard drive and power LED wires need to be placed in the proper polarity position.
    I have often noticed when the fan and motherboard lights flash momentarily, it is caused by a 4 or 6-pin connection from the power supply to the motherboard near the processor that is not connected or not connected properly.

    ... and Skoberlink,
    ther is no reason to quote a reply right next to that reply
     
Topic Status:
Not open for further replies.


Add New Comment

TechSpot Members
Login or sign up for free,
it takes about 30 seconds.
You may also...


Get complete access to the TechSpot community. Join thousands of technology enthusiasts that contribute and share knowledge in our forum. Get a private inbox, upload your own photo gallery and more.