Is this motherboard shot?

Discussion in 'Motherboards' started by killem2, Feb 16, 2010.

  1. Glider

    Glider Coastermaker

    126
    0
    May 4, 2009
    Belgium
    And what about paint, that every case has? Your calculation is way off, and makes no sense at all... CPUs use 1.5Vish, but the motherboard only recieves 3.3, 5 and 12V, the stabilisation and lowering of the voltage is done on the motherboards (by the FETs), no case needed for that...

    The reason the case is held at the same potential as the ground is because 2 metal objects in close proximity, but isolated are a capacitator, which can discharge and cause voltage spikes. Please, get your facts straight...

    EDIT: I missed your direct question;

    YES they are the best ground you'll ever have, because they are directly connected to the PSU ground, which is the reference of it all...
     
  2. 2Tired2Tango

    2Tired2Tango Tech Monkey

    632
    0
    Mar 8, 2009
    Ontario Canada
    Ummm... are you really sure you want to have this argument with a 30 year experienced design level technologist? Any idea how many technicians I've trained in my day?

    Really... I don't care a rats ass if you use U, E or V as the symbol for voltage, the math is correct. Ohms law does include power calculations...

    Give yourself some education... http://www.allaboutcircuits.com
     
  3. Glider

    Glider Coastermaker

    126
    0
    May 4, 2009
    Belgium
    Yeah, being a Master of Science in Electromechanical engineering, I would love to... Any idea how much idiots I met on fora?

    I don't mind about the name of the var, I do mind if you totally misuse the representation.

    http://en.wikipedia.org/wiki/Ohm's_law

    P=U*I (which ISN'T Ohms law BTW), can calculate the power drain, and the amps... And what does that tell you? Nothing...

    But I'll give you some calucation to do, since you like it. (I'll use SI Units, so it is calculated easily). A 1m, standard 2.5mm2 wire connected directly to PSU and Motherboard has how much resistance? And a case, connected to both, but with 2 (at least) connection resistances of 1Ohm (best case) is how much more?

    Please, educate me, or at least, amuse me ;-)
     
  4. 2Tired2Tango

    2Tired2Tango Tech Monkey

    632
    0
    Mar 8, 2009
    Ontario Canada
    And where does the return current go? That's right... it ALL goes through the ground system. You do understand that wire has resistance don't you? At 50 amps or more even a fraction of an ohm can result in quite a nasty voltage offset... Ohm's law, remember?

    Ok, do you really want me to agree with that? Seriously... You are talking about a couple of picofarads in an environment with fractional ohms of impedence...


    Which is EXACTLY why I recommended he add ground straps

    GEES!
     
  5. Glider

    Glider Coastermaker

    126
    0
    May 4, 2009
    Belgium
    Ah, the ground system, you mean all those black wires running back to the PSU? Because if that wouldn't be the ground system, how does it all work when the PSU isn't in the case?
    Ever felt 1picoFarad at 220V? Ever measured how much static can build on stuff? In excess of 1kV with ease... Ever seen what that does to rectifying gear like FETs? And thanks for educating me, I tought impedance occured in AC circuits, and resistance in DC, but thanks for the update... I'll go throw away my diploma now...

    Which is exactly why I said the case is not a part of the electrical circuit, and does not influence it at all. And ground straps? Wires running back to the PSU, they are included in the wiring for a reason, black wires, remember ;-)
     
  6. 2Tired2Tango

    2Tired2Tango Tech Monkey

    632
    0
    Mar 8, 2009
    Ontario Canada
    Ok... take a deep breath here...

    I offered a suggestion that I KNOW helps system stability and might actually solve this guy's problems... and he seems to be having quite a few since he built that wooden case.

    You are all lining up to argue mintuia with me...

    Ask yourself how this helps the OP solve his problem.

    Put it back in your pants boys.... I'm outa here!

    ROB... Kill my account, scramble the password... whatever. I'm done with this bunch of fuckups.
     
  7. Glider

    Glider Coastermaker

    126
    0
    May 4, 2009
    Belgium
    If you would read the OP, it isn't his computer ;) So there goes your argument...
    No, I just can't stand people offering "advice" that is as wrong as saying that the earth is flat... If you can prove me wrong, feel free to do so (with proof), but giving arguments like "I am a techie for 30 years" doesn't leave an impression... Well, it does, but not a good one :D Should I provide you some papers on the wiring standards so you can read up why there are so many black wires in a PC?
    About as much as your advice about the case is going to help him, not much... But your ramblings about Amps and Voltages might leave an impression on my cat, but it hardly makes it correct, nor reality...
     
  8. killem2

    killem2 Coastermaker

    198
    0
    Jan 5, 2010
    Welp, tried the full 9 yards tonight. I tried my PSU, no video signal. Tried my ram, with my psu, no signal, tried his psu and his ram in my pc, booted up fine. Swapped hard drives, mine worked his failed, tried gfx one more time, same thing worked in mine, would not work in his. I couldn't try anything else though, since his is an AM2 board and I am intel, so we bought a new motherboard. Jetway, cheapest they had on newegg, since he wasn't exactly rolling in the money. So we hope that will fix it.

    And yes, its my buddies pc that is out not mine. I am putting most of the money on that he's a very very heavy smoker and when I cracked that case open he's got tar and dirt build up a mile thick and he' sonly had the pc a year and a half.
     
  9. Kougar

    Kougar Techgage Staff Staff Member

    2,588
    0
    Mar 6, 2008
    Texas
    I hate to say it but if your board booted with his PSU and RAM, then it probably wasn't your board. When you say you tried your PSU, do you mean a new PSU or your PSU in his computer? I'm trying to follow but it gets confusing rather fast. Hope that replacement board works for you Killem.

    As the other argument is OT I won't get into depth with it, but suffice to say the PSU housing is grounded to the 3rd plug. The metal case grounds to the PSU housing, and the motherboard uses a grounding plane to attract stray unwanted voltage that it grounds through the screws. Inspect the screw holes on a motherboard as you can see they are designed to ground via solder contacts... (metal screws, brass risers, metal motherboard tray, etc). Same as opening a PSU housing, you will find a single wire grounding the PSU housing to earth. Is the connection required to function, no, but it does allow some particularly leaky/high noise ultracheap motherboards otherwise function without strange behavior. The official ATX specification PDF will discuss how things like the I/O cover is supposed to ground EMI to the case in addition to brief mentions of the actual chassis ground. ;)
     
  10. killem2

    killem2 Coastermaker

    198
    0
    Jan 5, 2010
    Ok let me re-explain I know I was a little confusing :p

    My friend computer won't show video signal from his 9600GT or on board.

    So what I have tested was.

    His GFX in my computer - It worked fine.
    His Ram in my computer - Worked Fine.
    His ram and gfx in my computer - worked fine.
    His ram and gfx and hard drive in my computer - Worked Fine.
    His ram and gfx and hard drive and psu in my computer - worked fine.
    His ram and gfx and hard drive and psu and dvd rom in my computer - worked fine

    I tried My gfx card, my hard drives, my ram, my psu, my dvd roms, basically any part that I could interchange between the computers and no matter what I would do, my friends pc, would not give video signal. It would boot up, you could hear the hard disk spinning, you could hear the fans moving, but that's it.
     
  11. crowTrobot

    crowTrobot E.M.I.

    84
    0
    Feb 8, 2010
    Toronto, ON, Canada
    That sounds like it leaves only the monitor as the problem then.
     
  12. Kougar

    Kougar Techgage Staff Staff Member

    2,588
    0
    Mar 6, 2008
    Texas
    Ahh, thanks for clearing that up Killem. :D

    Pretty safe bet it was his board then!
     
  13. killem2

    killem2 Coastermaker

    198
    0
    Jan 5, 2010
    I hooked the monitor up to my pc and it worked. With his gfx and mine. :)
     
  14. killem2

    killem2 Coastermaker

    198
    0
    Jan 5, 2010
    lol you guys won't believe it hahaha.


    So I get the new motherboard, works great, however of course he wants his old data, and windows vista is throwing a fit in normal mode and safe mode because of the new hardware so i hook his hard drive up to my pc and pull everything from it. Awesome, while I am doing that I crank back up his pc and reinstall vista for him.

    After its done, I copy the stuff from the hard drive back to the his, and go to start it all back up..

    SAME ERROR, NO SIGNAL TO VIDEO.

    Ok at this time I am about to throw his pc out the window. I fiddle with the power supply, make sure its all connected, and when I as up close to it, I hear a faint whining (imagine like a turbine going) really really really faint though you had to have your ear up to it and nothing else going. This was when the power was off (pc wasn't turned on) so I thought hmm.. I go to plug in my pc to his power strip.

    It looked pretty old, like from late 80s, it was heavy duty lol, metal 16 plug strip. So I plug my pc into it, and I GET THE THE SAME ERROR.

    So I plug my power strip I brought over, mine boots up fine. HIS BOOTS UP FINE. And just for shits and grins, I put his OLD MOTHERBOARD back in, with the new power supply... and ... wait for it..


    IT ALL WORKED lol.


    He was soo mad. So just to make sure it wasn't the power strip, i plug his back in, and go to reset it, and flip the on off switch and hear this

    :D:D



    [email protected][email protected] SZHZZHZHhzzzhhvh! Of electrical maddness come from it. So I unplugged it and dropped it right in the trash. He is going to keep the motherboard though, he didn't want to go through the hassle of returning it.

    But I thought it was hilarious that his pc problems were coming from an old ass power strip. He's been running 24/7 now since sunday when we installed the new motherboard and did all this. Working great.
     
  15. Kougar

    Kougar Techgage Staff Staff Member

    2,588
    0
    Mar 6, 2008
    Texas
    Damn, wow. I'm going to have to remember that one... people collect power strips and NEVER toss them, and so many are made as cheaply as possible... it is a bit scary that a basic power stripe would even make ANY audible noise, I would have trashed it and not dared plug anything into it lest it blow and damage something with it!

    Well, at least there's a bright side. His old motherboard still works. I hope he invests in a good quality power strip this time. :D
     
  16. Rob Williams

    Rob Williams Editor-in-Chief Staff Member Moderator

    12,080
    1
    Jan 12, 2005
    Atlantic Canada
    Whoa, I can't believe that the entire issue was caused by something so unbelievably simple. Ouch. That said, I have found that a lot of people really don't put the care into things like this as they should. I would NEVER trust a power bar that for one, looks crappy, and two, is old as heck. It's just not worth taking any chances... not when they cost about $10 to replace.

    Either way, it's really great to have the problem figured out, and I'm sure your friend learned a valuable lesson ;-)
     
  17. crowTrobot

    crowTrobot E.M.I.

    84
    0
    Feb 8, 2010
    Toronto, ON, Canada
    lol. wow. At least the power strip didn't fry any of your stuff!
    There are some faulty bootleg power strips they sell in small local hardware stores that turn out to be "fakes" from China, the cops raided a warehouse full of them up here a few months ago.
     
  18. killem2

    killem2 Coastermaker

    198
    0
    Jan 5, 2010
    Yeah I laughed my ass off, and now I have ammo for when he gives me crap about leaving the plastic cover on his heatsink for his cpu when I was installing it and the pc kept restarting.
     

Share This Page