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my cpu shows black screen no bios please help

By aznskater51
Dec 10, 2005
  1. yeh i just resolved an issue and happy so everything turns on great but at start up screen nothing comes up the monitor picks up the signal but just pitch black. how can i get to the bio screen if its doing this? help would be appreciated thanks
     
  2. DonNagual

    DonNagual TechSpot Ambassador Posts: 2,404

    Hello again! ;)

    There is a chance that you have fried your motherboard (from trying to turn it on without the riser pins installed).

    Here's what I would try (and confirm) before RMAing the board.
    1. Reset CMOS using the jumpers (look in your manual). If your board doesn't have CMOS reset jumpers, then unplug all power, and take the CMOS battery out for a half hour.
    2. Can you test parts on another computer? Are you sure your monitor works? What about that video card? What is it? Does it require a connection of its own to the PSU? (many do).

    Probably a good idea to list your system components in detail.
     
  3. aznskater51

    aznskater51 TS Rookie Topic Starter Posts: 21

    i doubt i fried the mother board but yes the board does have something called jcmos i have no idea how to use it though. u mind steping me through it? thanks
     
  4. gary_hendricks

    gary_hendricks TS Rookie Posts: 107

    If your monitor is going black, its probably a video card problem. Have you tried using another video card.
     
  5. DonNagual

    DonNagual TechSpot Ambassador Posts: 2,404

    You'll have to read your motherboard to reset cmos. There are typically 3 tiny pins lined up somewhere on your motherbaord, with a jumper connecting (for example) the two pins on the right. You remove the jumper and connect (for example) the two pins on the left then back to original position to reset the cmos.

    If you can't get in after that, then what you'll need to do is:

    1. Give us a detailed list of your parts. In this case, particularly your ram speed, CPU, graphics card and motherboard make/model.
    2. Give us a detailed description of what happens when you try and power up. What lights are lit up on the motherboard? Any beeps? Any fans spinning? As we can not physically inspect your system, you have to be the eyes. As much detail as possible please.

    Assuming your monitor works, my guess is one of the following:

    1. Mismatched ram
    2. Video card faulty
    3. You toasted your motherboard when you turned it on without the riser pins installed.
     
  6. aznskater51

    aznskater51 TS Rookie Topic Starter Posts: 21

    yeh there are 3 pins and a yellow thing cover the right 2 pins so all i gotta do is move that to the left 2 pins?
     
  7. DonNagual

    DonNagual TechSpot Ambassador Posts: 2,404

    I highly recommend you read your manual.

    But as a blind guess, it sounds like you have found the CMOS jumpers. Typically you move that jumper to the left 2 pins for a few seconds, then move it back to the original position.

    Be sure you unplug ALL power first, including the connections from your motherboard to the PSU.
     
  8. aznskater51

    aznskater51 TS Rookie Topic Starter Posts: 21

    i switched the cmos jumper to the left two for bout a minute and put back to the right 2. so i just replug in all my power plugs and reboot?
     
  9. DonNagual

    DonNagual TechSpot Ambassador Posts: 2,404

    Correct. If you in fact have the correct jumpers for resetting cmos, you are doing it right.
     
  10. aznskater51

    aznskater51 TS Rookie Topic Starter Posts: 21

    this kind of wonders me how it would reset itself without power. how is that?
     
  11. aznskater51

    aznskater51 TS Rookie Topic Starter Posts: 21

    and at the moment im gonna wait bout 20 min to replug my power cords but incase this does not work how would i know that my mother board would be fried. like any signs of this happeneing? and the ram is in fact the right ddr 266 matched with the mother board i made sure of that
     
  12. DonNagual

    DonNagual TechSpot Ambassador Posts: 2,404

    Good question, but it is how it is done. I can only assume that we are shorting SOMETHING by moving that jumper. It forces the BIOS to its default settings.

    Perhaps someone can give you the basics on WHY this works without power, but I ain't that guy ;)

    No need to wait 20 mins. You only have to wait that long if you DON'T have jumpers and are removing the battery. Moving the jumper to the other position for about 30 seconds is all it takes.
     
  13. DonNagual

    DonNagual TechSpot Ambassador Posts: 2,404

    To put it simply, if after ruling everything else out, the only thing left is dead motherboard.

    So you want to try and test everything one at a time. That is why I am asking you these questions above:

    To help us help you to troubleshoot. Without the answers to the above questions, I am afraid I can help no further.
     
  14. aznskater51

    aznskater51 TS Rookie Topic Starter Posts: 21

    crap nothin i dont think the mother board is fried because the fan is running for both the power supply and the cooler for the proccessor. here are the details a 256 mb ddr 266 ram. 250 gb hard drive. EPOX EP-5VKMI Via Socket 775 MicroATX Motherboard and an Intel Celeron D 346 3.06Ghz Processor. and a dvd burner. and a Ultra 350w V-Series PSU i hope this help please reply as quickly as possible. thanks
     
  15. DonNagual

    DonNagual TechSpot Ambassador Posts: 2,404

    Need to know this first:

    Are all these parts NEW?

    Do have another system you can test parts in?
     
  16. DonNagual

    DonNagual TechSpot Ambassador Posts: 2,404

    Also (IMPORTANT)

    What make/model is your AGP card?
     
  17. aznskater51

    aznskater51 TS Rookie Topic Starter Posts: 21

    yes i just got these items from tigerdirect.com today and all parts are new
     
  18. aznskater51

    aznskater51 TS Rookie Topic Starter Posts: 21

    just a wonder but would this also happen if i put the ram in the wrong socket cuz theres 2 of them and i put one to the riight not the left
     
  19. DonNagual

    DonNagual TechSpot Ambassador Posts: 2,404

    As a test of your motherboard you could also try removing everything from your motherboard. Absolutely everything. CPU, fans, memory, and then sit your case on a box beside your case and hook up your case speaker and the power supply, nothing else.

    Then using a screwdriver, touch the two pins that usually go to the cases "power on" switch. By shorting those pins it'll power your board on, and the board will send some beeps to your speakers. Those beeps are a code used to diagnose your board.
     
  20. bsihra

    bsihra TS Rookie

    The battery on the mobo retains CMOS settings when mains power is off. So by moving the jumper momentarily clears the CMOS to factory settings.

    Regarding your problem now - I once had a similar situation on a friend's PC. Believe it or not it was a dodgy modem. Do you have a modem fitted? If so, then remove it and reboot PC
     
  21. aznskater51

    aznskater51 TS Rookie Topic Starter Posts: 21

    donnugal can u explain the screwdriver shortening simpler? im not comprehending that too well
     
  22. aznskater51

    aznskater51 TS Rookie Topic Starter Posts: 21

    actually i tried it and i got no beeps what so ever :-( this mean my mobo is fried huh
     
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