System energizes, cpu fan spins, no display

Discussion in 'CPU, Motherboards and Memory' started by ramseyrt, Oct 11, 2008.

  1. ramseyrt

    ramseyrt Geek Trainee

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    Hello,

    I have an e-machine T2984 that died recently. I simply turned the system off three weeks ago and it never turned on again. Looking inside the case, the motherboard shows a lit green led but the system doesn’t energize. Looking on the web, this is a popular problem with this model of system. Other owners attributed this problem to a bad motherboard. I tested by power supply by shorting the green power connector wire to ground and the power supply fan spins and the CDROM and HD energize. I suspect that I have a good power supply. So, I replaced my mobo with a Biostar P4M80-M4. This board should be a drop-in replacement for my previous board.

    After replacing the mobo and energizing the system the CPU and case fan come on but I get no display. I have to hold the power button in for two or three seconds to get the system to power back down. I replaced the CPU (3Ghz Celeron) with another CPU (3Ghz P4) with the same results. I also tried different RAM ( I have 2 sticks of 512Mb PC-2700) and installed a 3rd party video card (PCI GeForce 6200). All tests result in spinning fans and no display.

    I replaced the Biostart mobo with another of the same model. This mobo is having the exact same problem. Again, I performed all of the same testing; replacing the CPU, swapping memory, and using a 3rd party video card.

    I've been double checking that the 20-Pin and 4-Pin cables are connected to the motherboard and that the CPU and case fans are plugged in. When swapping out the CPUs I make extra sure that the CPU is seated correctly and that there's a proper amount of thermal paste between the CPU and heat sync.

    What am I missing? I find it highly unlikely that both CPUs are bad, both motherboards are bad, both DIMMs are bad, or that I have a bad power supply. I've tried resetting the BIOS jumper on both boards and I've re-installed both boards in the case to make sure I didn't short them out.

    --------------(Posts from two separate days on another support forum)------------

    So, I bought a new power supply today, installed it in the case with the Biostart mobo, and I'm having the same issue. So, I took everything out of the case and started my testing on a piece of particle board. I know I don’t have the ideal ESD environment but I’m really trying to touch the power supply frequently and wood doesn’t conduct. I don’t have the luxury of having a full ESD bench at home : )

    The only components I’m working with now are the mobo, CPU, one stick of RAM, and the new power supply. I tried both CPUs in the Biostar mobo with the new power supply and I also tried both pieces of RAM. Every test results in the same spinning fan condition without a BIOS screen.

    Out of curiosity, I tried these same tests with my original E-Machine mobo. It never energizes in any way other then the green led on the mobo. It must be toast.

    I've tried two of everything; two CPUs, two motherboards, two pieces of RAM, and two power supplies. So, two of something I’m using must be bad. What kind of hardware failure would cause my symptom? I'm going to try and get another CPU and piece of RAM to test with but it might take me a day or two.

    I have two CRTs and two LCDs that I’ve been switching back and forth with. All four displays work on the other two working computers I have. I’m using a CRT for most of my testing if that’s of any consequence.

    My tests have followed this pattern:

    Two Weeks ago…
    Biostar MOBO #1 - Celeron 3Ghz CPU - DIMMs #1 - Original PSU
    Biostar MOBO #1 - Celeron 3Ghz CPU - DIMMs #1 - Original PSU - GeForce 6200 PCI
    Biostar MOBO #1 - Celeron 3Ghz CPU - DIMM #1 - Original PSU
    Biostar MOBO #1 - Celeron 3Ghz CPU - DIMM #1 - Original PSU - GeForce 6200 PCI
    Biostar MOBO #1 - Celeron 3Ghz CPU - DIMM #2- Original PSU
    Biostar MOBO #1 - Celeron 3Ghz CPU - DIMM #2 - Original PSU - GeForce 6200 PCI

    Biostar MOBO #1 - P4 3Ghz CPU - DIMMs #1 - Original PSU
    Biostar MOBO #1 - P4 3Ghz CPU - DIMMs #1 - Original PSU - GeForce 6200 PCI
    Biostar MOBO #1 - P4 3Ghz CPU - DIMM #1 - Original PSU
    Biostar MOBO #1 - P4 3Ghz CPU - DIMM #1 - Original PSU - GeForce 6200 PCI
    Biostar MOBO #1 - P4 3Ghz CPU - DIMM #2- Original PSU
    Biostar MOBO #1 - P4 3Ghz CPU - DIMM #2 - Original PSU - GeForce 6200 PCI

    I sent the Biostar mobo back to the vendor as DOA after all of the tests above failed.

    Two Days ago I got another mobo from eBay…
    Biostar MOBO #2 - Celeron 3Ghz CPU - DIMMs #1 - Original PSU
    Biostar MOBO #2 - Celeron 3Ghz CPU - DIMMs #1 - Original PSU - GeForce 6200 PCI
    Biostar MOBO #2 - Celeron 3Ghz CPU - DIMM #1 - Original PSU
    Biostar MOBO #2 - Celeron 3Ghz CPU - DIMM #1 - Original PSU - GeForce 6200 PCI
    Biostar MOBO #2 - Celeron 3Ghz CPU - DIMM #2- Original PSU
    Biostar MOBO #2 - Celeron 3Ghz CPU - DIMM #2 - Original PSU - GeForce 6200 PCI

    Biostar MOBO #2 - P4 3Ghz CPU - DIMMs #1 - Original PSU
    Biostar MOBO #2 - P4 3Ghz CPU - DIMMs #1 - Original PSU - GeForce 6200 PCI
    Biostar MOBO #2 - P4 3Ghz CPU - DIMM #1 - Original PSU
    Biostar MOBO #2 - P4 3Ghz CPU - DIMM #1 - Original PSU - GeForce 6200 PCI
    Biostar MOBO #2 - P4 3Ghz CPU - DIMM #2- Original PSU
    Biostar MOBO #2 - P4 3Ghz CPU - DIMM #2 - Original PSU - GeForce 6200 PCI

    Today’s testing with a new power supply…
    Biostar MOBO #2 - Celeron 3Ghz CPU - DIMM #1 - New PSU
    Biostar MOBO #2 - Celeron 3Ghz CPU - DIMM #2- New PSU

    Biostar MOBO #2 - P4 3Ghz CPU - DIMM #1 - New PSU
    Biostar MOBO #2 - P4 3Ghz CPU - DIMM #2- New PSU

    I’m being as thorough as I can possibly be. I’ve poured a lot of time and a growing pile of money into this. Would a bad piece of RAM or a bad CPU cause the kind of problem I’m experiencing?

    I’d appreciate any help,

    Rob
     
  2. 3321thec

    3321thec Geek Trainee

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    Does the board give any reports as to what it may be doing? Some MOBOs I know have LEDs that will give status codes. If yours doesnt have this, it should at least beep if it is POSTing correctly.

    To me, this sounds like a bad video card. Looks like the system is booting, your just not getting any video from it. If the MOBO has any integrated video, try using that.

    Let me know how it goes,
    ~3321thec

    (P.S. Sorry for anything that doesn make sense, I am extremely tired at the moment, so just ask for clarification)
     
  3. ramseyrt

    ramseyrt Geek Trainee

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    Unfortunately the Biostar motherboard doesn’t have any LED indictors. It also doesn’t have an onboard pezo speaker, and I don’t have a PC speaker, so I can’t get the beep codes. I’m probably going to pick up a PC speaker today for this purpose.

    I performed the following tests this morning using another 3rd party video card, as a suggestion from another forum:

    Biostar MOBO #2 - Celeron 3Ghz CPU - DIMM #1 - New PSU – ATI Rage 128 PCI
    Biostar MOBO #2 - Celeron 3Ghz CPU - DIMM #2- New PSU – ATI Rage 128 PCI

    Biostar MOBO #2 - P4 3Ghz CPU - DIMM #1 - New PSU – ATI Rage 128 PCI
    Biostar MOBO #2 - P4 3Ghz CPU - DIMM #2- New PSU – ATI Rage 128 PCI

    I also tried resetting the BIOS jumper again. All tests end with the same result. Spinning fan with no display.

    I am trying people suggestions to if you have one please post!

    Thanks!

    Rob
     
  4. DataSavers Com

    DataSavers Com Geek Trainee

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    From the day the very first Emachine PC hit my workbench there have been power supply problems.
    As a matter of fact my floor is littered with Emachine cases from the first model to the present.
    One thing has been a constant in all these years, power supply malfunction.
    On some, the power supply blows the motherboard, on others it simply self destructs and the motherboard survives.
    But the most common scenario is that both the motherboard and power supply die together. The problem is actually pretty simple, though still deadly for the hardware.
    A typical cheaply made Emachine power supply will work flawlessly until one of 2 things occur.
    1. you turn off the switch at the back of the machine
    or
    2. you unplug your emachine with it either running or off.

    What happens is that your Emachine is in a constant warm up or (ready) state much like an instant on TV set. The power supply isnt actually on at full power but it's still active, waiting for you to hit that little silver E.
    Most PC's are designed this way, but the Emachine has it's own idea of how things should be done.
    Unlike a well made power supply, which will absorb and or bleed off the stored voltage from your motherboard capacitors when the power switch is turned off and the power button is pressed, an Emachine will not allow the excess voltage discharged from your capacitors to shunt to the ground which runs to your power outlet earth or ground wire.
    Depending on the power supply used on your particular Emachine, the voltage may either accumulate in the power supply's larger capacitors and dump back to the motherboard which hasn't been turned on yet, not allow the capacitors to discharge at all, or dump their OWN high voltage capacitors stored voltage onto the motherboard itself.
    This results in swollen or ruptured Capacitors and a dead or semi dead motherboard.
    The solution is, and has always been, replace that power supply before it ruins your budget!
    But on a lighter note, An Emachine makes a pretty door stop.
     
  5. ramseyrt

    ramseyrt Geek Trainee

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    Sady, I never was able to get the second mobo working so I sent it back to the eBay seller. Unfortunately I had to eat the cost of shipping. I suppose that's how it goes.

    I tried the second Biostart mobo with a new power supply and it behaved exactly the same as with the eMachine power supply. I've found several other posts with complaints about this model of mobo stating the same behavior.

    I haven't gotten a third board yet. When I do, I'll make sure I use my new power supply first!

    Thanks,

    Rob
     

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