Optiplex GX280 won't boot - fan goes to high speed

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Optiplex GX280 won't boot - fan goes to high speed

  • Hi All -

    I've got a GX280 that had a failed PSU and HD (they failed some time ago).  I just put in a replacement PSU.  It's a PS-5161-1D1S, with a SATA connector soldered on from the original failed PS-5161-7DS.  I also put in a replacement HD (WD1600-AAJS).

    The system won't boot.  In fact, it doesn't even seem to get through POST.  The Power button is solid amber, no beeps, no diagnostic lights, fan quickly goes to maximum speed.  It's a lot like the issue described here:

    http://www.dellcommunity.com/supportforums/board/message?board.id=Desktops_Workstation_Optiplex&message.id=4922&query.id=145564#M4922

    I've tried the same steps outlined in that thread, and the system still won't boot.  Like the other thread, I think the mobo is probably bad on my gx280.

    Just for kicks, I grabbed a random ATX Power Supply and tried it with the same results.

    Before I buy a replacement Mobo, My questions:
    1. Does this motherboard specifically requie a PS-5161-7DS, or should any generic ATX power supply work?
    2. Is it possible the CPU could be bad?  I know that's unlikely, but I was just wondering if anyone else has seen similar behavior from a bad CPU.


    Thanks!
    Noah
  • it's the motherboard. Check for swollen caps.
  • Hi Artizen -

    > it's the motherboard. Check for swollen caps.

    Thanks for the reply.  None of the caps looks discolored, swollen or popped.  That's one reason why I wanted to double check before I buy another mobo.  I just don't want to spend another $50 to find that I also need to replace the CPU.  By that point I could have bought a whole used system and still had this one for parts.

    Anyone know about the PS question - there's nothing special about the stock PS is there?  I can use another model of power supply that fits the case, right?


    Thanks!
    Noah
  • From what I've ready, bad capacitors don't always swell/burst and in many cases don't give up visual clues that they're bad. The symptoms seem to suggest something similar.
  • It's not the motherboard.  I just replaced it and it's the same story.  $50 buck and an hour of time wasted.  Oh well. 

    It's either the PS or the CPU.  I'm leaning toward the PS, but does anybody have something more than a guess as to which it is?  I don't want to do any more guessing.

    Maybe somebody has the answer - will any random Power Supply work in this machine, or is there some proprietary requirement for the stock Power Supply (PS-5161-7DS)?


    Thanks,
    Noah
  • You asked about using a PSU from another model. I believe the GX280 uses a 24 pin PSU when many of the earlier Dell Optiplex/Dimension/Precision models use a similar PSU but a 20 pin connector (more readily available). I'm pretty sure it uses the same PSU as the Dimension 8400 and probably lots of other Dell models. The GX270 (and all the Dimension and Precision equivalents) use 20 pin connectors. That being said, you can score 20->24 pin adapters pretty cheap (I'm actually using a 24->20 adapter on my GX270 in order to use an aftermarket 470 watt PSU).

     

    A PSU would be my next step if I was troubleshooting.

     

    Good luck and let us know what you find. Keep in mind that you will experience fit issues with many aftermarket PSUs. Search around the site to see what works in the aftermarket. Dell loves their proprietary parts.

    Message Edited by btc64 on 02-07-2008 07:45 PM
  • Hi bct64 -

    Thanks for the reply.  The GX280 motherboard has the older  20 pin ATX 1.0 connector for the PS, and the replacement Power Supply I used is a PS-5161-1D1S, which I think is the one that comes with the GX270.  It has the same 20 pin connector.  I also tried another power supply I had lying around and the problem was still there.  Unfortunately, I don't have another CPU lying around.

    I guess that leads me to believe it's the CPU that's bad, but how often do you see a CPU go bad?  I've seen computers absolutely fried by lightning that still had functional CPUs.


    Thanks,
    Noah
  • I stand corrected on the PSU. I have a GX280 at work and never counted! It shares so many similarities with the 8400. I think the 8400 has a 24 pin. Re: CPUs, I've seen socket 775 CPUs go fairly cheap on eBay, but if that doesn't work, then what?

     

    I'm watching this thread out of interest for my PC at work. If you get a new CPU, just don't get a 570J or 670 (both 3.8 Ghz). I can't get either to work with the GS280.:smileymad:

  • Hi Again bct64 -

    > I stand corrected on the PSU. I have a GX280 at work and never counted!

    I think the desktop variety of gx280 may have the 24 pin PS connector. This one is the small form factor version.


    > I'm watching this thread out of interest for my PC at work. If you get a new CPU,
    > just don't get a 570J or 670 (both 3.8 Ghz). I can't get either to work with the
    > GS280.:smileymad:



    Ah, thanks! Good to know! I think I'll probably get a 2.8ghz model off of ebay. I found one for $30.


    > but if that doesn't work, then what?

    I dunno. Probably sell off the working parts and buy a GX520 or something similar.


    Thanks for the help. I'll let you know if the CPU works.

    - Noah
  • I always forget about the other formats in the GX2XX series. I've got SMT format across the board in my "Frankendells" (see my sig) and the GX280 at work is also SMT.
  • "It's not the motherboard. I just replaced it and it's the same story. $50 buck and an hour of time wasted. Oh well. "

    My apologies. Thos symptoms were classic motherboard failure indicators.
  • > My apologies. Thos symptoms were classic motherboard failure indicators.

    No worries!  That's what I was thinking, too.


    - Noah

  • To anyone who's interested.  Replacing the processor didn't help either.  I forgot to mention that my next steps might include kicking this stupid thing.  Maybe it's something in the electronics on the case?  In any case, I've wasted too much time and money on this pile o' garbage.  I'm going to buy a working machine and sell off these parts.  Anyone interested in a spare motherboard, processor or PS for a GX-280?