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New mobo and case won't turn on

Discussion in 'Hardware' started by syc0path, Mar 1, 2006.

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  1. syc0path

    syc0path Thread Starter

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    My buddy got a new mobo, new case, and new RAM. We pulled the rest of the stuff out of his old case and put it all together, but we can't get it to turn on. He said that if he unplugs the power cord, plugs it back in, and then hits the power button, it runs for like a second before it shuts down again. After that, hitting the power button again has no effect unless u unplug/plug the power cord again.

    We did have a problem removing the processor from the old mobo... a couple of the prongs got bent, but I straightened them and it felt like everything slid into place when I *gently* installed the processor in the new mobo. There could also be a problem w/ the RAM... the reason why he bought a new mobo was becuz he put DDR2 RAM in the old mobo and the mobo and the DDR2 RAM got fried. His old DDR RAM was also installed at the time. We installed both the new DDR RAM (not DDR2!) and the old RAM in the new mobo before we 1st tried to turn it on. Since then, he has experimented w/ different combos of RAM, using only 1 stick, etc, but to no effect. But I don't think either the processor or the RAM is the problem, becuz it doesn't seem to run long enough to even get to them.
     
  2. happyrck

    happyrck

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    look and see if when you turn the power on that the processor fan starts spinning...if not your processor is overheating and is shutting down trying to keep from frying itself or it already committed suicide
     
  3. syc0path

    syc0path Thread Starter

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    No, it only runs for less than second. Even if the fan wasn't running, that's not enough time to get the heatsink so hot that it can't cool the chip.
     
  4. norton850

    norton850

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    If you have an AMD processor and something's wrong with the cooling, like heat sink on wrong, fan not working or no thermal compound, it doesn't take very long to overheat and shutdown. So double check that and if your sure it's OK take the MB out of the case and set it on the box it came in. Attach just one stick of RAM, the CPU/HS and fan and power. You don't need video at this point. Actually you probably dont need the RAM either.
     
  5. Triple6

    Triple6 Moderator

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    Or it could be as simple as problem with the power switch. There are motherboards that power on for a second or two as soon as they recieve power then power off. I believe its so the Wake-on events can occur.

    Try shorting the two power switch pins instead of using the power switch. All you need to do is use a screw driver to connect the two pins for a second to start the POST.
     
  6. syc0path

    syc0path Thread Starter

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    Yeah I thought about the power switch, and about putting a paper clip between the prongs to jump between the pins to check it. But my understanding from talking to him was that it didn't kick on when he plugged it in -- it only kicks on when he plugs it in and then pushes the power button. So the mobo is getting a signal from the switch, it just doesn't stay on for more than a second.

    BTW, it's a 2.8GHz P4 processor.
     
  7. happyrck

    happyrck

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    this is the post.(.power on self test) sequence

    AMI BIOS POST Errors

    During the POST routines, which are performed each time the system is powered on, errors may occur. Non-fatal errors are those which, in most cases, allow the system to continue the boot up process. The error messages normally appear on the screen. Fatal errors are those which will not allow the system to continue the boot-up procedure. If a fatal error occurs, you should consult with your system manufacturer or dealer for possible repairs. These errors are usually communicated through a series of audible beeps. The numbers on the fatal error list correspond to the number of beeps for the corresponding error. All errors listed, with the exception of #8, are fatal errors. All errors found by the BIOS will be forwarded to the I/O port 80h.

    * 1 beep: DRAM refresh failure. The memory refresh circuitry on the motherboard is faulty.
    * 2 beeps: Parity Circuit failure. A parity error was detected in the base memory (first 64k Block) of the system.
    * 3 beeps: Base 64K RAM failure. A memory failure occurred within the first 64k of memory.
    * 4 beeps: System Timer failure. Timer #1 on the system board has failed to function properly.
    * 5 beeps: Processor failure. The CPU on the system board has generated an error.
    * 6 beeps: Keyboard Controller 8042-Gate A20 error. The keyboard controller (8042) contains the gate A20 switch which allows the computer to operate in virtual mode. This error message means that the BIOS is not able to switch the CPU into protected mode.
    * 7 beeps: Virtual Mode (processor) Exception error. The CPU on the motherboard has generated an Interrupt Failure exception interrupt.
    * 8 beeps: Display Memory R/W Test failure. The system video adapter is either missing or Read/Write Error its memory is faulty. This is not a fatal error.
    * 9 beeps: ROM-BIOS Checksum failure. The ROM checksum value does not match the value encoded in the BIOS. This is good indication that the BIOS ROMs went bad.
    * 10 beeps: CMOS Shutdown Register. The shutdown register for the CMOS memory Read/Write Error has failed.
    * 11 beeps: Cache Error / External Cache Bad. The external cache is faulty.
     
  8. JohnWill

    JohnWill Retired Moderator

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    Remove the MB from the case and try firing it up on the bench with just the memory and video card, no other peripherals or cards. Get that running first, put it in the case the same way and get it running there. After that runs, add all the other stuff.
     
  9. happyrck

    happyrck

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    If you have access to KNOWN TO BE GOOD power supply try swapping them
    has the new motherboard got a 24 pin or a 20 pin connecter and how many Watts is the power supply
     
  10. 1_rob_1

    1_rob_1

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    New mobos are often supplied with the clear bois jumper across the wrong pins to save battery life, check that this is not the prob.
     
  11. max 8

    max 8

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    It's the connections from the power supply most probably. Make sure only the main power connector is plugged in from the psu to the mobo. Dont plug in those extra little square 4pin or 6pin power connectors to the mobo. I had the same problem in the past.

    Hope this helps.
     
  12. syc0path

    syc0path Thread Starter

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    Well max wins the prize... kinda. I disconnected the 4pin connector from the power supply and it fired right up. I suspect that the mobo is expecting different polarity than the plug provides (although the diagram in the mobo's manual indicates that it should match). That would explain why it would start for a split second and then stop -- some sort of protection circuitry would kick in and shut it down. And once it knew about the problem, it wouldn't start up again -- until we pulled the power cord and erased the memory.

    Anyway, we thought we had it figured out... until we hooked everything back up. The computer seems to run fine now, except that the monitor isn't getting a signal -- not even a flicker. We tried a spare vid card to no avail. But both vid cards are AGP, so it could still be a problem w/ the AGP port on the mobo. Given that the AGP port is close to the 4-prong power connector (and presumably uses a fair amount of power) is it possible that disconnecting the 4-prong connector is preventing the AGP slot/card from getting sufficient voltage to operate?

    I put my voltmeter on the 4-prong connector, and it's putting out a solid 11.96V. I thought about rearranging the wires in the connector to experiment w/ different polarities, but I didn't wanna fry anything.
     
  13. Rockn

    Rockn

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    Did you take the MB out of the case like JW suggested? You could still have the MB shorted to the case with an improperly placed MB standoff.
     
  14. JohnWill

    JohnWill Retired Moderator

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    I figured he'd come to that at some point...
     
  15. norton850

    norton850

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    Sounds familiar somehow:D
     
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