No POST after upgrading PSU

By HyukeN
Jun 9, 2011
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  1. I installed some new hardware: PSU and a harddrive, so I had removed my video card while doing this. I put everything back together and the computer booted and worked fine for about 1 - 2 hours before I turned it off for the night.

    In the morning my computer powered on, but the monitor was all black and the power light on the monitor was just blinking. The BIOS POST was long-short-short (video card issue). I looked in the case and one of the wires was blocking one of the two fans on the GPU. I tied this wire out of the way and the same symptoms occurred.

    Next I tried to turn it on and the red overclock light and all blue LEDs on the motherboard turn on along with all the fans and the motors in the hard drives. There is no POST however and the monitor light only blinks. There is no sound of windows starting up. I cannot power down with the power button or reset using the reset button.

    After reseating everything and trying alternate cords, monitors, keyboard, mouse, CMOS battery, video card, and memory I have determined it must be the motherboard (most likely), case, or CPU(least likely). I even testbenched it by taking everything out of the case and putting it on boxes. So it doesn't appear that there are any shorts from the motherboard to the case.

    I have also figured out a way to get the computer on after many hours of trial and error. I followed these exact steps:

    1. power down with PSU switch
    2. hold power button for 30 seconds
    3. remove battery
    4. hold power button for 30 seconds
    5. remove power cord
    6. hold power button for 30 seconds
    7a. put battery back in
    7b. put power cord back in
    8. flip PSU switch back on
    9. turn computer on
    10. Wait upto 5 minutes and then computer will boot 90% of the time, but not give POST beep

    This worked for a couple weeks, but everytime I unplugged the computer (or maybe when switching off the PSU switch) or it was shut down improperly the same symptoms would come back. However, lately I have these symptoms every time I shut down the computer properly plus now my system clock is running slow. I tried an older CMOS battery but I get the same results.

    I'm thinking either the current and old CMOS battery are both bad, or there is a problem with the motherboard (compatibility issue maybe?). Is there anything else I can try before I spend money to RMA this board? Should I try a BIOS update or does the system clock point to hardware failure? Note that I initially only had problems when starting up the computer and recently the system clock runs slow and the system tray is a little bit screwed up (it doesn't show all my normal icons running in the background, but it has white space for where they should be and I cannot click on the 2 or 3 that are showing up properly).

    One last thing to note is that I had a similar problem with my last build which used the same case, speakers, keyboard, mouse, and monitor until I bought a new motherboard, then never had the problem again. RMA'ing that motherboard multiple times never solved it.

    Motherboard: MSI 870A-G54
    Video Card: Gigabyte Radeon HD 6850
    Power Supply: upgraded to Antec Truepower 650W from Enermax Noisetaker 420W
    CPU: AMD Phenom II X2 555
    RAM: G.SKILL Ripjaws PC3-10666 2X2GB
    CASE: Coolermaster CAC-T05 Centurion 5 Aluminum
  2. Mark56

    Mark56 TechSpot Paladin Posts: 1,886

    A slow clock is usually a sure sign that the CMOS battery needs to be replaced, so do that first (with a new one). Removing the battery will have set it back to defaults so go into the Bios and check it is recognising all the hardware and you have it set correctly for the type of hard drive, IDE or SATA. And check the voltages for RAM and CPU are set correctly.

    The hard drive details are missing from your specs as is the version of Windows you are using.

    You said you had a similar problem with another motherboard which you RMA'd multiple times, where are you getting your parts from? Are you using second hand items?

    Is the recently fitted CPU and hard drive second hand or new?

    Your video card may have been fried when the fan was jammed, when you swapped it with another card was that a known good working card, have you got another PC you can test the card in. Also try running the PC with the onboard graphics for now and remove the card.

    Is the OS installed on the new hard drive and did you get all the chipset drivers for the motherboard installed?
  3. HyukeN

    HyukeN TS Rookie Topic Starter

    I have replaced the CMOS battery twice (from two different packs of batteries) and have the same results.

    OS: Windows 7 SP1 64-bit
    HDD: The HD with the OS is a Maxtor 200Gb SATA 1 (I think)
    HDD2: Maxtor 250GB SATA 1 (I think)

    I am getting my parts from NCIX (Canada). They are new and I was RMA'ing a Gigabyte board in my last build until I finally gave up and purchased an MSI board to replace it and it fixed my woes. Everything in the build is new except for: case, peripherals, hard drive, optical drives.

    The PSU (I think that is what you meant) is new and the HD I added was a non-OS HD. It is used, but the problem persists even when I take the second HD out.

    There are no onboard graphics. I believe this is more of a booting problem and all the internal LEDs stay lit and the red OC LED stays lit when I have this problem. I get these same symptoms if I remove the Video Card or use an alternate Video Card (known working).

    The OS is still installed on the first HD. The hardware changes were: switched PSUs and added a 2nd HD. I don't recall doing anything with chipset drivers. But when I can get the computer on and into the OS I have no troubles interfacing with either HD.
  4. Mark56

    Mark56 TechSpot Paladin Posts: 1,886

    Hi, and welcome back.

    Taking into account all the things you have tried I have listed below three tests for the memory, hard drive and CPU. The first two use a boot disc so that should work ok but the CPU test will require getting the PC to boot to the desktop if you can still get it there. If you can't get on-line to download the software do it on another PC and transfer the program on a flash drive or re-recordable CD.


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