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2 DOA's in a row? Wtf... are we doing something wrong?

By pyromaster114
Mar 2, 2010
  1. Okay so my friend ordered parts for a new computer, and we were like "yay! parts!" and proceeded to assemble the thing.
    We hit the power button, and the thing turned on, and shut off, turned on, shut off, etc etc.
    So we eventually determined the motherboard was dead. We sent it back to Newegg, and they promptly sent us ANOTHER one.
    It did the exact same thing.

    So we're on try number 3, and we're paranoid that somehow between the 2 of us, we must be doing something wrong.
    Is there something I'm missing that could be causing this problem to occur again and again?

    We've tested the 3rd motherboard without putting it in the case we plan to use, and it appears to work. We don't want to f*ck this one up.

    The reason I think something may be wrong with the way we're putting it in the case is because the case is rather odd (in comparison to what I've seen...) in that instead of having those little screw-in studs / standoffs that are gold-ish in color (usually), it has raised portions of the tray (basically little bumps with screw holes).

    The case is a XION AXP100-001BK RT. I don't get what we could be doing wrong... we were both trained in school for this stuff... myself more hardware and her more software... but I figure it can't help to ask at this point.

    You can see the odd little raised sections of the tray (which are fairly common on lots of cases these days except I've never dealt with them personally...) here http://www.newegg.com/Product/Product.aspx?Item=N82E16811208027 in the pictures.
     
  2. Route44

    Route44 TechSpot Ambassador Posts: 11,966   +70

    You've got to have those stand-offs otherwise you will be shorting the board out against the tray. The standoffs should have come with the motherboard and/or the case.
     
  3. pyromaster114

    pyromaster114 TS Guru Topic Starter Posts: 246

    We HAVE some standoffs, plenty in fact... but the case's motherboard tray has several built in standoffs, if we were to screw standoffs into those it would raise the motherboard too high above the tray and the ports on the back would not line up with the hole in the case's back panel.... so I can only assume we're not supposed to screw in standoffs to those bumps.

    Check the Newegg link I posted and look at the pictures of the case... you can see the little raised bumps I'm talking about... should I put plastic washers inside the case between the built in standoffs and the board? (That sounds like a not so good idea to me but someone I was talking to mentioned that they had to do that for a board one time...)
     
  4. Route44

    Route44 TechSpot Ambassador Posts: 11,966   +70

    If you avoided those "bumps" how many standoffs could you install? Enough for stability?
     
  5. Matthew

    Matthew TechSpot Staff Posts: 5,268   +92

    If you've tested the motherboard outside the case with success, then your motherboard is almost definitely making contact inside the chassis -- and those built-in standoffs could be to blame.

    Your only practical options would be to place something non-conductive between the contact point(s) or get another case. You might want to make sure that your motherboard's holes line up with the stand-offs properly. For instance, there might be a standoff in a spot where your motherboard doesn't have a hole.

    Frankly, I'd RMA the case, but I imagine you must be tired of that at this point :).
     
  6. pyromaster114

    pyromaster114 TS Guru Topic Starter Posts: 246

    Okay well I've put some non-conductive tape over the built-in standoffs.
    This way, the only way that the thing will have contact, is through the screw itself, which we will be placing a non-conductive washer between the screw head and the board.

    So there's no way this is going to short to the case now... right?
     
  7. Route44

    Route44 TechSpot Ambassador Posts: 11,966   +70

  8. pyromaster114

    pyromaster114 TS Guru Topic Starter Posts: 246

    Thanks to Matthew for suggesting the non-conductive stuff.

    The motherboard still works now inside the case.
    OS is installed and everything.
     
  9. Route44

    Route44 TechSpot Ambassador Posts: 11,966   +70

    Good to hear. How is it running?
     
  10. captaincranky

    captaincranky TechSpot Addict Posts: 11,703   +1,887

    There really is no justification for having to tape the motherboard and standoffs.

    I've seen cases that have a similar arrangement to yours, but basically, the standoff "pegs" were more similar to the brass screw-in types, than the bubbles in the case photos at Newegg,

    That said, I recall a motherboard that would actually short out if you put all the standoffs in. Since you can't avoid all the mobo standoffs in your case, it does give one pause to wonder.

    There are plenty of decent 40 dollar case buys around, and I really wouldn't mess around with junk.

    Newegg doesn't always get it right with product. Recently, they sold an H55 Gigabyte mobo with an Intel i5-750 CPU in a bundle. People installed the CPU, then couldn't figure why the boards wouldn't work. Well, H55 socket boards require a CPU with integrated graphics, or you have to install a video card. Th i5-750 doesn't have integrated graphics, so a couple of dozen customers were sitting around wondering "where the picture went", so to speak. RMA the case.
     
  11. mailpup

    mailpup TS Special Forces Posts: 6,980   +362

    I have that exact same case. By coincidence I'm using it now and I've had no such trouble with the raised bumps as built-in standoffs. So while there might be a short somewhere, it's not necessarily due to the bumps themselves, IMHO. I didn't use any paper washers or other insulating materials. The motherboard I installed is an MSI P45 Neo3.

    I don't really have a explanation for the cause of your problem. I'm only posting to mention my experience with your case. Just curious, what motherboard are you using?
     
  12. captaincranky

    captaincranky TechSpot Addict Posts: 11,703   +1,887

    Actually, case standoffs are ground terminals. I had a Foxconn (?) P-945 board, which required that a standoff be omitted. I figured it out before I fried the board, but this was in a case with brass removable standoffs. I'm not saying that this is definitely an issue here, just that it can happen.

    You do need to have the board and case grounded together, since that's part of the RF emission controls

    And no, you shouldn't have to use tape, bubblegum, or shoelaces to get your box up in running.

    Given the back story here, there exists the possibility that a little knowledge is a dangerous thing. I'm jus' sayin'.
     
  13. SNGX1275

    SNGX1275 TS Forces Special Posts: 10,715   +397

    Indeed, I've built a relatively few number of systems (probably about 10?) compared to pretty much everyone else here with over 500 posts, but EVERY system I've built has used standoffs, and 2 or 3 of them had paper washers included so I also used them (between the motherboard and the screw, not sure if its even feasible to use them between the board and the standoff).

    This is the first I've heard of systems failing if you use standoffs.
     
  14. pyromaster114

    pyromaster114 TS Guru Topic Starter Posts: 246

    While I realize that using tape to get the thing running is probably less than desirable, make that not a good idea, it worked.

    The previous boards have been confirmed to be DOA at this point. Bad luck I guess?
    This third board didn't work when we first put it in the case, so we took it out, tested it (and found that it worked) and put it back into the case using the slightly ghetto-ish tape and washers.

    The motherboard should still be grounded because the screws do touch the metal of the case (via the shaft of the screw) and the screw heads do touch the little contact points that are meant to ensure the motherboard is grounded... so I assume we should be okay.

    I believe the problem we were having stems from some small pins on the bottom of the board, from the components mounted on top of it, that were just barely touching the tray in some way... this quite obviously triggered a fail safe because of a short, and the board refused to function.

    Thanks to everyone for your help and comments. The machine is functioning amazingly well, definitely worth the wait (lol almost a month at this point). The quad core processors from Intel are amazing... I'll be upgrading my gaming desktop to a quad core when I can afford it. (Not that I really play games... just need to beat out my friend lol)
     
  15. captaincranky

    captaincranky TechSpot Addict Posts: 11,703   +1,887

    If you have a board laying aroung, have a good close look at it. You'll see that there are solder lands where the retaining screws. where there is solder, I believe that they are at ground potential. There are other screw holes in a board that do not have these lands. I think that they may need the paper washers. Still, some of the screws contact the board ground. This is the same effect as being in a tunnel with your cell phone, the case absorbs RF emission and since it is also connected to the ground of the AC house wiring, it suppresses the RF, preventing RFI. So, the board is grounded to the case, the case is grounded to earth, literally.
     
  16. Appzalien

    Appzalien TS Rookie Posts: 94

    All it takes as mentioned above is one standoff where the mobo doesn't want one and you have a short. Those star like or rings of solder are actually meant to be grounded to the case and if they are absent then the engineers did not want that hole being used so no solder is applied. The problem is is there is an actual stand off position that lines up with that stupid hole and if you don't spot it your screwed, cause they will not admit they did that and put it in the manual like they should. I had an Abit board that had one of those holes that lined up, had no solder and was not meant to be used. But you will never hear about it on the Abit site, you have to find it in peoples comments in forums like this when someone actually figures it out on their own.

    In your case (I have seen cases with the bumps toward the back, and flat holes forward for brass standoffs when the board is really wide) if one of the bumps was molded into the case in a position where the engineers do not want a screw, your only choice is to insulate the bump as you have and use no screw. But (and thats a big BUTT) do not insulate all the standoffs as the grounding of the mobo protects it during accidental shorts and surges.

    Using no screw in one of the bumps should not be a problem as its height alone is enough to support the board when pushing things in but not necessarilly pulling them out (cards). So memory slots would not be effected since you don't really pull memory, just push it.
     
  17. xietianhua001

    xietianhua001 TS Rookie

    good job thanks
     
  18. captaincranky

    captaincranky TechSpot Addict Posts: 11,703   +1,887

    Well, we're all glad that you've got it worked out and running.

    As an afterthought, the "dimples" that your case has as standoffs, are (IMO) horrible engineering, since the rather wide contact area they present to the board is ripe for disaster.

    Anyhoo, save your pennies for a bit, and put the whole mess into an Antec 900, then you'll be really, really, happy with your new computer. (Or at least one or two more "reallies" than you are now).
     
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