Page 1 of 3 123 LastLast
Results 1 to 15 of 31
  1. #1
    5 Star Lounger
    Join Date
    May 2003
    Location
    Sterling Heights, Michigan, USA
    Posts
    633
    Thanks
    0
    Thanked 1 Time in 1 Post

    Blown Motherboard

    Had a call from a community center I do tech support for, that they had a couple of Dell Inspiron desktops that "weren't working." When I got over there they admitted there'd been a couple momentary power outages lately. First Dell's onboard Ethernet port was dead, and an add-in card fixed that.

    Second Dell appears to power up, but no video. Tried an add-in video card, still no picture. Replaced the power supply, when power is turned on, the fans spin up for a couple seconds, then stop. The fans spin up again for a couple seconds, then stop. Third time they spin up they keep running, but nothing else happens. Does this pattern suggest any problem in particular?

  2. #2
    3 Star Lounger bassfisher6522's Avatar
    Join Date
    Jul 2013
    Location
    NC
    Posts
    373
    Thanks
    53
    Thanked 40 Times in 39 Posts
    Yep...either the CPU and/or mobo is fried. Power outages usually send electrical spikes and it's those spikes that do the damaged by overloading the circuitry of the electronic component. This is why is so important to use a high quality surge protector and a UPS (uninterruptible power supply).

    There is no known way of diagnosing a bad/fried cpu/mobo with software or hardware. The only way is to exchange the components of the exact same make/model to verify if it's working correctly or not.

    I'd start with the CPU....as the mobo is getting power to spin up the fans.

  3. #3
    WS Lounge VIP
    Join Date
    Dec 2009
    Location
    Earth
    Posts
    8,191
    Thanks
    48
    Thanked 984 Times in 914 Posts
    Methinks it's time for a replacement. Those sort of power problems tend to magnify over time - the damage is subtle and over time more things fail.

    cheers, Paul

  4. #4
    Super Moderator jwitalka's Avatar
    Join Date
    Dec 2009
    Location
    Minnesota
    Posts
    6,794
    Thanks
    117
    Thanked 799 Times in 720 Posts
    When you replaced the power supply, did you install the 4/8 pin ATx connector? Forgetting that will result in those symptoms.

    Jerry

  5. #5
    5 Star Lounger
    Join Date
    Mar 2011
    Posts
    820
    Thanks
    16
    Thanked 62 Times in 57 Posts
    The crucial question is: did the hard drive survive? You can put that in an enclosure and recover all of their data, and program installations for that matter. On the other hand, if they were performing regular backups they already have (most of) it.

  6. #6
    WS Lounge VIP Coochin's Avatar
    Join Date
    Jun 2014
    Location
    Queensland, Australia
    Posts
    2,154
    Thanks
    31
    Thanked 307 Times in 267 Posts
    Quote Originally Posted by JJDetroit View Post
    ...Second Dell appears to power up, but no video. Tried an add-in video card, still no picture. Replaced the power supply, when power is turned on, the fans spin up for a couple seconds, then stop. The fans spin up again for a couple seconds, then stop. Third time they spin up they keep running, but nothing else happens. Does this pattern suggest any problem in particular?
    You could try resetting the BIOS/CMOS (I have seen this problem w/ many PCs, especially after power surges).

    1. Unplug the mains power from the power supply unit.

    2. Remove the CMOS battery from the motherboard.

    3. Use a suitable screwdriver (or some other suitable metal object) to short out the +/- contacts in the CMOS battery holder.

    4. While the +/- contacts are shorted, press and release the PCs power-on switch 8 to 10 times (forces the motherboard to load the backup copy of the BIOS and resets the CMOS settings to defaults).

    5. Refit the CMOS battery and plug the mains power back in.

    6. Power on.

    If you now have video, you will need to look at the BIOS settings (date, etc.). If not, then the motherboard is probably dead.

    WARNING: many newer computers do not have a BIOS; instead they have a UEFI (Unified Extensible Firmware Interface); UEFI might commonly be called "UEFI BIOS", but strictly-speaking it is very different to the older BIOS technology; I would avoid using the above procedure on a UEFI computer, at least until more information about UEFI becomes available.

    2014-10-30 Have since successfully used this procedure to reset the UEFI on the motherboard in a Win8.1 PC.

    Note (22 November 2014): this procedure relies on residual power stored in the motherboard's capacitors, so it is important to perform each step as quickly as possible especially after removing the mains power lead and the CMOS battery.
    Last edited by Coochin; 2014-11-22 at 00:34. Reason: more info
    Computer Consultant/Technician since 1998 (first PC was Atari 1040STE in 1988).
    Most common computing error is EBKAC: Error Between Keyboard And Chairback
    AMD FX8120 (8-core @ 3.1GHz) CPU, Gigabyte GA-990FXA-D3 motherboard, 8GB (2x4GB) DDR3 1866MHz RAM, ATI-AMD Radeon HD6770 PCI-E VGA, 480GB Kingston SSD, 2TB Seagate SATA3.0 HDD, ASUS DVD/RW.

  7. #7
    Super Moderator RetiredGeek's Avatar
    Join Date
    Mar 2004
    Location
    Manning, South Carolina
    Posts
    9,435
    Thanks
    372
    Thanked 1,457 Times in 1,326 Posts
    Coochin,

    I'm no EE so I don't understand how your procedure above will accomplish anything w/o any Power. Could you please explain how/why this works? Inquiring minds want to know...and so do I.
    May the Forces of good computing be with you!

    RG

    PowerShell & VBA Rule!

    My Systems: Desktop Specs
    Laptop Specs

  8. #8
    Super Moderator jwitalka's Avatar
    Join Date
    Dec 2009
    Location
    Minnesota
    Posts
    6,794
    Thanks
    117
    Thanked 799 Times in 720 Posts
    RG, it drains all power form the capacitors. I've seen 3 different laptops recently that looked totally bricked - no display when pushing the power button that I fixed with a similar procedure:
    Disconnect the power cord from the wall socket
    Remove the battery
    Hold the power button down for 10 seconds to drain the caps
    Restore the power cord and viola the laptop boots

    Haven't seen this on a desktop though.

    Jerry

  9. The Following User Says Thank You to jwitalka For This Useful Post:

    RetiredGeek (2014-10-09)

  10. #9
    Super Moderator RetiredGeek's Avatar
    Join Date
    Mar 2004
    Location
    Manning, South Carolina
    Posts
    9,435
    Thanks
    372
    Thanked 1,457 Times in 1,326 Posts
    Jerry,

    Thanks that's great to know and understand!
    May the Forces of good computing be with you!

    RG

    PowerShell & VBA Rule!

    My Systems: Desktop Specs
    Laptop Specs

  11. #10
    WS Lounge VIP Coochin's Avatar
    Join Date
    Jun 2014
    Location
    Queensland, Australia
    Posts
    2,154
    Thanks
    31
    Thanked 307 Times in 267 Posts
    Quote Originally Posted by RetiredGeek View Post
    Coochin,

    I'm no EE so I don't understand how your procedure above will accomplish anything w/o any Power. Could you please explain how/why this works? Inquiring minds want to know...and so do I.
    As jwitalka implies in his #8 post, the procedure uses the residual power stored in the motherboard's capacitors to trigger the BIOS/CMOS reset (note that the CMOS battery +/- contacts need to be shorted out for this to work).
    Computer Consultant/Technician since 1998 (first PC was Atari 1040STE in 1988).
    Most common computing error is EBKAC: Error Between Keyboard And Chairback
    AMD FX8120 (8-core @ 3.1GHz) CPU, Gigabyte GA-990FXA-D3 motherboard, 8GB (2x4GB) DDR3 1866MHz RAM, ATI-AMD Radeon HD6770 PCI-E VGA, 480GB Kingston SSD, 2TB Seagate SATA3.0 HDD, ASUS DVD/RW.

  12. #11
    WS Lounge VIP Coochin's Avatar
    Join Date
    Jun 2014
    Location
    Queensland, Australia
    Posts
    2,154
    Thanks
    31
    Thanked 307 Times in 267 Posts
    Quote Originally Posted by jwitalka View Post
    ...
    Remove the battery...
    Your procedure will drain any residual power from certain capacitors and thereby clear the laptop's RAM, but it probably won't force a BIOS/CMOS reset because the laptop's CMOS battery is still powering the CMOS chip.

    To use the procedure in my #6 post to force a BIOS/CMOS reset can mean having to almost completely dis-assemble the laptop to get access to the CMOS battery; however better-designed laptops these days usually have the CMOS battery somewhere near the RAM chips or under the keyboard where it is easy to get at.

    I have rescued many laptops using the procedure in your #8 post, but in several cases I had to use the procedure in my #6 post (succeeded in all but one case - that laptop had the CMOS battery soldered to the motherboard and it was too old to be worth the hassle).

    It might help to explain what BIOS and CMOS are: BIOS means "Basic Input-Output System" (IOW a program), and CMOS means "Computer Memory On Silicon" (IOW a silicon chip); the BIOS is programmed ("resident") in CMOS; when the motherboard is powered-on the BIOS executes and initialises the various "buses" and attached devices; VGA is initialised early in this process (obviously you need to see what's going on).

    Until about the early 1990s most motherboard's CMOS were not easily re-programmable; back then if a BIOS upgrade was needed, or if the BIOS became corrupted, it was usually necessary to remove the CMOS from the motherboard and have it re-programmed by an electronics engineer using a special device. Big hassle.

    Since then manufacturers began to use "flash" chips for CMOS. These "flash" CMOS chips can be re-programmed in-situ, which is what you are doing when you download and install a BIOS upgrade from your computer manufacturer's support website.
    Computer Consultant/Technician since 1998 (first PC was Atari 1040STE in 1988).
    Most common computing error is EBKAC: Error Between Keyboard And Chairback
    AMD FX8120 (8-core @ 3.1GHz) CPU, Gigabyte GA-990FXA-D3 motherboard, 8GB (2x4GB) DDR3 1866MHz RAM, ATI-AMD Radeon HD6770 PCI-E VGA, 480GB Kingston SSD, 2TB Seagate SATA3.0 HDD, ASUS DVD/RW.

  13. #12
    Super Moderator jwitalka's Avatar
    Join Date
    Dec 2009
    Location
    Minnesota
    Posts
    6,794
    Thanks
    117
    Thanked 799 Times in 720 Posts
    All I can say is that it worked every time I tried it and is the procedure and is the recommended procedure by HP:
    http://h10010.www1.hp.com/ewfrf/wc/d...name=c01684768

    Jerry

  14. #13
    3 Star Lounger
    Join Date
    Mar 2010
    Location
    USA
    Posts
    301
    Thanks
    65
    Thanked 39 Times in 30 Posts
    @Coochin
    Great post.

    Reminder: PC/laptop is hardier than you think.
    When lightening strikes, or power line spike hits, and your PC/laptop does not boot, don't immediately go out and buy a new motherboard or a new PC. Follow procedures posted here. Reset the corrupted BIOS. Might save you a bundle ...
    It is also an excuse to tame over your wife's objection for a brand new PC toy!

  15. #14
    WS Lounge VIP Coochin's Avatar
    Join Date
    Jun 2014
    Location
    Queensland, Australia
    Posts
    2,154
    Thanks
    31
    Thanked 307 Times in 267 Posts
    Quote Originally Posted by jwitalka View Post
    All I can say is that it worked every time I tried it and is the procedure and is the recommended procedure by HP:
    http://h10010.www1.hp.com/ewfrf/wc/d...name=c01684768

    Jerry
    The HP article you link to in your post applies to laptops. The intent is to clear all data stored in memory (i.e.: RAM - "Random Access Memory"). It will not force a BIOS/CMOS reset.

    The only mention of BIOS is in the opening paragraph, "Resetting your computer forces the system to clear and re-establish the software connections between the BIOS and the hardware".

    Certainly, try the procedure in the HP article and in your #8 post first. But if that doesn't work then try the BIOS/CMOS reset in my #6 post before you throw the beast in the bin.
    Last edited by Coochin; 2014-10-09 at 20:47. Reason: more info
    Computer Consultant/Technician since 1998 (first PC was Atari 1040STE in 1988).
    Most common computing error is EBKAC: Error Between Keyboard And Chairback
    AMD FX8120 (8-core @ 3.1GHz) CPU, Gigabyte GA-990FXA-D3 motherboard, 8GB (2x4GB) DDR3 1866MHz RAM, ATI-AMD Radeon HD6770 PCI-E VGA, 480GB Kingston SSD, 2TB Seagate SATA3.0 HDD, ASUS DVD/RW.

  16. #15
    Silver Lounger wavy's Avatar
    Join Date
    Dec 2009
    Location
    ny
    Posts
    2,377
    Thanks
    235
    Thanked 147 Times in 136 Posts
    Ok now I don't want to ruffle any feathers, you are good folk but my recollections are different...
    Well let me pre edit here as I was writing this I did a quick Wikipedia check and what I believe may no longer be true

    -CMOS is an acronym for Complimentary Metal Oxide Semiconductor; a volatile memory.

    -The BIOS is not stored in CMOS, the BIOS is stored on Non Volatile Ram (NVRam, Electrically Erasable Programmable ROM ) which like a flash drive will keep its memory contents even w/o power. It will require power to change its contents.

    -The parameters used by BIOS to program itself (setup options) are stored in CMOS which is maintained by the little disk battery.

    Now here lies Danger Will Robinson

    -Removing the battery will allow the info stored in CMOS to dissipate. Shorting the terminals could not hurt and would speed up this process. The result will be a reset to defaults stored in BIOS NVRam.


    Apparently this later is no longer true!

    [URL="http://en.wikipedia.org/wiki/Nonvolatile_BIOS_memory"]

    To access the BIOS setup when the machine fails to operate, occasionally a drastic move is required. In older computers with battery-backed RAM, removal of the battery and short circuiting the battery input terminals for a while did the job; in some more modern machines this move only resets the RTC. Some motherboards offer a CMOS-reset jumper or a reset button. In yet other cases, the EEPROM chip has to be desoldered and the data in it manually edited using a programmer. Sometimes it is enough to ground the CLK or DTA line of the IC bus of the EEPROM at the right moment during boot, this requires some precise soldering on SMD parts. If the machine lets one boot but does not want to let the user into the BIOS setup, one possible recovery is to deliberately "damage" the CMOS checksum by doing direct port writes using DOS debug.exe, corrupting some bytes of the checksum-protected area of the CMOS RAM; at the next boot, the computer typically resets its setting to factory defaults. For example:

    c:\debug
    -o 70 10
    -o 71 aa
    -q
    have not seen the debug command in a decade !!
    Learn something new every day, probably forget it tomorrow

    PS that HP article to me seems to be a clearing of CMOS because AFAIK "Ram" would not need clearing. The article is a bit bewildering and I am not seeing the mechanism for clearing CMOS w/o removing the disk battery unless it is NVRam being cleared by the power button being pressed. This would jive w/ Coochin's technique.


    [/SIZE][/FONT]
    Last edited by wavy; 2014-10-09 at 21:14. Reason: PS & clarity
    David

    Just because you don't know where you are going doesn't mean any road will get you there.

Page 1 of 3 123 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •