Welcome to PCForumz.com!
FAQFAQ      ProfileProfile    Private MessagesPrivate Messages   Log inLog in

Abit NF-7 v2 mobo - Won't power up (looks like damaged mic..

 
   Hardware Problem Solving Community! (Home) -> ABIT RSS
Next:  abit aw9d-max  
Author Message
Vanguard

External


Since: Dec 26, 2006
Posts: 5



(Msg. 1) Posted: Wed Jan 24, 2007 6:58 am
Post subject: Abit NF-7 v2 mobo - Won't power up (looks like damaged micro-capacitor chip)
Archived from groups: alt>comp>periphs>mainboard>abit (more info?)

Motherboard = Abit NF7-S version 2.0

Got a new AGP video card (ATI x850) but had problems getting out the
old card and putting this one in. Poor design of the case. For card
slots with connectors near the top, the top retaining nut/screw must be
removed to allow angling out the card (the card slot opening doesn't go
all the way to the top). In trying to remove the old card or put in
the new card, it looks like I might've damaged a surface-mount
capacitor (marked "C1" on the mobo).

Now the system won't power up. Occassionally when I hit the
front-panel Power switch, the fans spin and the front LEDs comes on but
only for a second. I left one hard drive attached, removed the 20-pin
PSU connector from the motherboard, and shorted PS-ON (pin 14, green
wire) on the PSU connector. The fans started spinning in the PSU and
the hard drive spun up, so it looks like the Fortron PSU is still
working. Something on the mobo is probably preventing the power up. I
went hunting around the mobo and noticed what looks like a damaged
surface-mount capacitor (tiny rectangular chip about 1/16" wide by 1/8"
long). It looks like it got crushed in the center. It is marked as
"C1" on the white silk screen printing on the mobo.

So one choice is to replace the mobo. Finding this mobo or other AGP
8x 400 FSB mobos is tough since most sellers have gone to PCI-e mobos.
However, I just upgraded to 2GB (from 512MB) and got the high-end AGP
video card to upgrade this system to keep it around for another couple
years. Replacing with a newer PCI-e mobo would mean having to also get
a new video card and new DDR2 memory. I can find some NF7-S v2 mobos
at eBay and replace the whole mobo but some sellers want hefty money
for this old mobo. That may be what I have to do since I don't know
how to repair the mobo.

I'm pretty good at soldering but this is a very tiny surface-mounted
chip. I don't know what is the capacitance. The electronics parts
site that carries just about every part type in the world is in my
Favorites on the drive in this computer and I don't recall their name,
but then I would need to know the exact part to figure out where in
their site they list it to then order a replacement. I'm not sure my
soldering expertise is sufficient for replacing surface-mount
components, especially ones so tiny that I can hardly see any details
of them. Since the mobo has to come out whether I repair or replace
it, I could try soldering in a new surface-mount capacitor chip but I'm
back to not knowing what to get for the part replacement. If I knew
the capacitance and type of capacitor was this tiny chip part, I
suppose that I could unsolder the chip and then solder on a regular cap
in its place by soldering its leads onto the mounting pads on the mobo.

I suppose I could take it to a computer shop and have them do the work
but their cost would be the same, or greater, than me getting a
replacement NF7-S v2 mobo. Right now I am only guessing that the
crushed looking C1 chip on the mobo (which feels chipped in the middle
and looks silvery as though some foil were exposed) is the culprit.
I've removed all components from the mobo except the CPU and PSU and it
still won't power on (I expect beeps for memory and video absence but
didn't hear any such beeps). I also tried with 1 and 2 stick of
memory and put back the old video card but still no power up (except
for the occasional 1-second "burp" when the fans will spin and the
front LEDs come on).

 >> Stay informed about: Abit NF-7 v2 mobo - Won't power up (looks like damaged mic.. 
Back to top
Login to vote
Vanguard

External


Since: Dec 26, 2006
Posts: 5



(Msg. 2) Posted: Wed Jan 24, 2007 11:18 am
Post subject: Re: Abit NF-7 v2 mobo - Won't power up (looks like damaged micro-capacitor chip) [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

>Sounds like you are just thinking out loud. Was there a > question in there somewhere?

Subject = ... Won't power up ...
Inferrence = How do I get it to power up?

I called a couple of local computer repair shops. They won't replace
surface-mounted chips on the mobo. That makes me leery that I could
accomplish what they won't even try. Also, I haven't found any info
telling me what is the capacitance for the micro-chip capacitor and
what construction type it is, so I wouldn't know what to replace it
with. Other gurus have mentioned that the idea of unsoldering the
onboard micro-cap and soldering on a regular cap using its leads won't
work due to timing issues

> Try this one:http://www.pcprogress.com/product.asp?m1=pw&pid=ABNF7%2DS2G

A bit pricier than what I've found using Froogle and definitely higher
than getting a replacement at eBay. If I end up replacing the mobo, I
might get the AN7 instead of another NF7-Sv2, but there are sellers of
both at eBay.

I started to wonder if shorting the PS-ON wire would work as a
permanent fix (rather than just to test the PSU works). The soft logic
on the mobo pulls PS-ON (pin 14, green wire) to low and that makes the
PSU come on. So what harm would there be in *permanently* shorting
PS-ON to ground?

Basically I would use a Scotchlok to splice the adjacent green PS-ON
and black (ground) wires at the connector. One problem with that
solution is the PSU wouldn't turn off when the connector was removed
from the mobo. I could instead wire-wrap those pins together on the
header on the mobo. This means the PSU would always stay on. Well,
that's better than a dead computer that's only dead because I can't get
the onboard soft-logic to pull low the PS-ON line.

 >> Stay informed about: Abit NF-7 v2 mobo - Won't power up (looks like damaged mic.. 
Back to top
Login to vote
Zadok

External


Since: May 26, 2006
Posts: 35



(Msg. 3) Posted: Wed Jan 24, 2007 12:46 pm
Post subject: Re: Abit NF-7 v2 mobo - Won't power up (looks like damaged micro-capacitor chip) [Login to view extended thread Info.]
Imported from groups: per prev. post (more info?)

Back to top
Login to vote
dmlarsen

External


Since: Jan 06, 2005
Posts: 30



(Msg. 4) Posted: Wed Jan 24, 2007 2:58 pm
Post subject: Re: Abit NF-7 v2 mobo - Won't power up (looks like damaged [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

VG,

I'm going through solving a similar "symptom" with my KT7-RAID....1 sec
burp, then shutdown....with the NG's help, I suspected bad caps, but the
replacement board did the exact same thing ! I was getting good numbers
at the PS device connectors when measured w/o load, but the minute I
checked it with my existing HD connected, I saw a rapid drop in the
device connector voltages, and shutdown. Weird thing is (to me, at
least !) was that, with an old Connor 420 meg HD attached, everything
booted just fine.

I'm no electrical engineer (that's obvious) and I can't say how the PS
"works", or what the differences are in power needs between a very old
IDE drive and a somewhat newer WD IDE drive (80 gig)...but in my
situation, a replacement of the PS seems to have fixed the problem
(haven't fully reassembled the system yet....)

If you have access to a different PS (I didn't, without tearing my
"main" system, or even worse, the wife's "main" system down !), you
might just want to hook it up and see what happens <g>. Might be
cheaper than a new/old mb, or even trashing your board by trying some
sort of repair on the suspect part !

Dean.....


Vanguard wrote:
>
> Motherboard = Abit NF7-S version 2.0
>

-snip-
 >> Stay informed about: Abit NF-7 v2 mobo - Won't power up (looks like damaged mic.. 
Back to top
Login to vote
Vanguard

External


Since: Dec 26, 2006
Posts: 5



(Msg. 5) Posted: Wed Jan 24, 2007 4:44 pm
Post subject: Re: Abit NF-7 v2 mobo - Won't power up (looks like damaged micro-capacitor chip) [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

I'll check the voltages under load. However, when it was loaded (which
is somewhat mandatory with ATX power supplies so they draw enough
current to stay turned on once the PS-ON line is shorted to ground), I
had 2 hard drives, floppy, and a DVD-ROM drive attached. Basically I
just pulled the 20-pin PSU connector from the mobo and shorted PS-ON to
ground so all the other components that don't get their power through
the mobo were still attached. The PSU's fan spun up and both hard
drives spun up. But I'll still check the voltages.
 >> Stay informed about: Abit NF-7 v2 mobo - Won't power up (looks like damaged mic.. 
Back to top
Login to vote
Vanguard

External


Since: Dec 26, 2006
Posts: 5



(Msg. 6) Posted: Thu Jan 25, 2007 10:55 am
Post subject: Re: Abit NF-7 v2 mobo - Won't power up (looks like damaged micro-capacitor chip) [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

I checked the voltages under load (using 2 multimeters). All were
okay. I then wanted to short across the tiny micro-cap chip to see if
that would let the latch circuit work for the soft-power button. I was
able to power up but also without shorting the pins across the cap.
All of a sudden the computer would now fully power up. When trying to
place the sewing pins (because they have tiny points to let me contact
the pads) across the cap and touch them to short across the cap, I
think that I ended up scrapping away some debris there between it and
the next micro-cap. Maybe it was conductive and causing a short.
Whatever, the computer now powers up. Crossing my fingers to hope it
stays that way.
 >> Stay informed about: Abit NF-7 v2 mobo - Won't power up (looks like damaged mic.. 
Back to top
Login to vote
Display posts from previous:   
Related Topics:
Abit KN8 CPU Fan header damaged? - I bought a new CPU (Athlon 3500+) motherboard (Abit KN8 regular). I bought a Gigabyte heatsink/fan and fitted everything together. On first power up I noticed that the CPU fan wasn't going round and on closer inspection noticed that it had been dropped..

What Abit mobo would you buy...? - Hi guys! I'm looking to build two new computers, one with an AMD Sempron CPU and one with a Celeron D CPU, so I'm wondering which are the best Abit mobos to get... Price should not be an issue, but the computers will be intended for office use only,...

Linux + USB + ABIT MoBo - Having learned the hard way that Via has trouble spelling USB correctly, I'm led to ask here "Which ABIT motherboards are supporting Linux with all USB functionality at par and painless?"

AMD 64 vs ABit Mobo's vs Win98SE - this post is not archived.

New Abit NI8 SLI mobo - Won't boot - A0 & C1 POST code - Just bought an NI8 SLI mobo. Did the following: - Connected it up with ALL THREE power connectors (ATX12V1, ATX4P1, and ATXPWR1). - Installed my CPU with stock cooler and connected to CPUFAN. - Installed my memory. - Setup the SLI bridge connector on the...
   Hardware Problem Solving Community! (Home) -> ABIT All times are: Pacific Time (US & Canada) (change)
Page 1 of 1

 
You can post new topics in this forum
You can reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum



[ Contact us | Terms of Service/Privacy Policy ]