Archived from groups: microsoft.public.windowsxp.hardware (
More info?)
Sometime on, or about Sat, 20 Nov 2004 23:26:43 -0600, Vanguard wrote:
> "Sam" <srs2_11BS@bsHotmailBS.com> wrote in message
> news:16czr5t2vzoze.1e5fp937l2tk3.dlg@40tude.net...
>> Sometime on, or about Sat, 20 Nov 2004 16:09:02 -0600, Vanguard wrote:
>>
>>> "Sam" <srs2_11BS@bsHotmailBS.com> wrote in message
>>> news:1n1yo7aof1tht$.els43w9ymtjb.dlg@40tude.net...
>>>>I had a perfectly fine working system until yesterday (Asus A7N8x-E
>>>>Deluxe,
>>>> Athlon XP3200+ with 2-512meg sticks of Crucial RAM and ATI Radeon
>>>> 9500). I
>>>> took out my motherboard and installed it in a new all-aluminum case.
>>>> Now it
>>>> won't boot past the opening splash screen.
>>>>
>>>> I've tried the following:
>>>>
>>>> Swapping the motherboard for another identical one, changing the
>>>> video
>>>> card, changing the cables and the power supply. I've disconnected
>>>> all
>>>> my
>>>> optical drives and the floppy, leaving nothing in the machine but
>>>> the
>>>> video
>>>> card and my primary hard-drive. I reset the CMOS, and tried booting
>>>> with
>>>> only one of my memory modules at a time. Finally, I put my
>>>> hard-drive
>>>> in
>>>> another machine and it booted just fine.
>>>>
>>>> The only thing left is the CPU... is this possible? If the CPU
>>>> fried,
>>>> I
>>>> wouldn't expect to see anything at all. But I"m open to ideas. Is
>>>> there
>>>> anything different in an all aluminum case that would be different
>>>> than the
>>>> standard ones? I sort of doubt that, since I tried to put everything
>>>> back
>>>> into the original case too.
>>>>
>>>> Nothing I've tried works... I've built about 12-15 computers before
>>>> and
>>>> never had this much trouble before. Thanks for any help.
>>>>
>>>> Sam
>>>> --
>>>> To mail me, please get rid of the BS first
>>>
>>> Presumably you are following anti-static procedures and haven't
>>> zapped
>>> the mobo. What happens when you remove the mobo, PSU, hard drive,
>>> and
>>> hook it together outside the case, like on a non-conductive desktop
>>> surface?
>>>
>>> Have you tried using insulating grommets/washers at the top of the
>>> metal
>>> standoff posts (so the fiber washer is between the standoff and the
>>> mobo)? Are the standoffs too fat and maybe touching a foil that runs
>>> way too close to the hole (which means you'll need insulating
>>> washers)
>>> or there is slop in positioning the mobo so the standoff's ledge
>>> overlaps the foil portion of the mobo? If you end up having to use
>>> insulating fiber washers, only use them where you have to. The hole
>>> near the backpanel plate should shorted to the case to provide a
>>> short
>>> path for ESD so it goes from the connectors to the case rather than
>>> traversing across the mobo. Have you tried using plastic standoffs?
>>> Have you checked the fingers on the backpanel plate (aka I/O shield)
>>> aren't sticking into a connector?
>>>
>>> Aluminum, tin, steel, they all conduct so it doesn't matter what is
>>> the
>>> metal. I've never fabbed a host that had the mobo mounted on a
>>> plastic
>>> or non-conductive base. In fact, about the only plastic in the case
>>> is
>>> the front cover; the rest is metal (except for a side panel with a
>>> window) and all of it is conductive.
>>>
>>> You talk about moving to a different *case* but never mentioned what
>>> happened to the power supply. Did you bring over the power supply
>>> from
>>> the working setup, or are you using the power supply that was
>>> included
>>> with the new case? Have you tried using the old power supply? Could
>>> be
>>> the new power supply is too weak. If it is a generic PSU, figure
>>> getting only two-thirds of its rated wattage; the good PSU actually
>>> provide more amperage than they are rated for, but the cheapies often
>>> do
>>> not make it past two-thirds of their rating. Does the mobo have a
>>> separate 4-wire power connector besides the 20-pin PSU connector? If
>>> so, does the power supply include that connector and did you connect
>>> it?
>>
>> I'm using the same power supply as before. It's a 460watt Enermax,
>> which
>> should have plenty of power. As I mentioned, I tried swapping power
>> supplies just in case, and it didn't make any difference.
>>
>> Sam
>> --
>> To mail me, please get rid of the BS first
>
> In another post in this thread, you said the system ran okay when
> "built" outside the case and you are using the same or better
> components, like the power supply, that worked before. Since it is
> working outside the case, it didn't get zapped. So I'm back to thinking
> the problem is with the standoffs.
>
> Do each of the motherboard holes for the standoffs have a solder patch
> around them (i.e., a circular shiny ring)? Are the standoffs smaller
> than this contact patch (i.e., for the "ledge" on the standoff on which
> the motherboard will rest)? Are you making sure not to use overly large
> screws that extend beyond this contact patch area around the hole (so
> the screws aren't shorting out some nearby foil on the surface of the
> motherboard)? I've had one case where the ledge of the standoff was too
> fat (these were really thick standoffs) and shorted to a foil outside
> the patch/contact area around the hole and another where the screws
> heads (used to affix the motherboard to the standoffs) were way too fat
> and shorted to a foil that ran past the contact area.
>
> There is another possibility. For a multilayer motherboard, it is
> possible the layers got offset or there is a short between the layers
> but only present under pressure (i.e., when you torque down the screws
> to affix the motherboard to the standoffs). What happens if you just
> lay the motherboard atop the standoffs but don't insert the screws?
> That way you don't risk shorting due to a fat standoff (although you
> might have to use some paper to insulate them when laying the mobo atop
> them) and also eliminates a short within the layers due to flexing of
> the mobo (since you said it worked okay when laid flat outside the
> case). What happens if you then gently flex the mobo by pressing on it
> in various locations? What happens if you then insert the screws but
> only very gently cinch them up by hand (so the screw just touches and
> snugs against the motherboard)? Got any screws with smaller heads? And
> then what happens when you torque up the screws to rigidly affix the
> motherboard to the standoffs?
>
> Presumably you have already checked for a long pigtail off the backside
> of the motherboard that might contact the case. What happens if you
> insert the motherboard but WITHOUT the I/O shield around the backpanel
> connectors? Have you checked if the sides of the motherboard are
> pressed against the case? Or if any of the components on the top of the
> motherboard (or bottom) are pinched up against the sides, the power
> supply, the drive chassis, or pressed against anything which would
> provide a contact or strain the component? I have seen electrolytic
> capacitors that worked when there was no strain on them but fail when
> pressed to the side because of a poor contact inside for its leads.
I had checked for all the obvious things... the back of the board (both of
them) was pretty smooth and the standoffs were long enough to prevent any
contact with the case. None of the sides of the board were touching the
case, except at the backplate. I ended up putting tape over the standoffs
and then using a fiber washer below the screw head. That seems to have done
the trick. Really strange, since I've built a couple of dozen machines
without this kind of problem in standard cases. I have one more machine to
set up in one of those Lian-Li PC-V1200 cases and I'm obviously going to
use the same insulating technique again.
One other thing I discovered was that if you're using CS (cable select) for
your hard drives, don't use a longer IDE cable. I found that the standard
18" worked fine, but a 24" didn't. (It didn't recognize the drive at the
end of the cable properly). I used the Master/Slave jumper settings and it
worked just fine.
Only one more problem to solve... the floppy drive is recognized by Windows
(no errors in Device Manager), but it doesn't see any disks that are
inserted and won't boot from a floppy. The light comes on when you put a
disk in and try to read it... but Windows doesn't see it and says: "Please
insert a disk into the drive A:"). BIOS has the drive setup properly. (I
swapped cables and checked the power connection). It's an old drive so I'm
going to put a new one in to see if that does the trick.
Sam
--
To mail me, please get rid of the BS first
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