PC Chips MB - will not initialize monitor

[who]

I build pc's for disadvantaged children from donated parts. I am by no means
an expert, but sometimes know what I am doing (maybe?). I had two pc's which
were in my house when the power was struck by lightning. They were not even
plugged in, but the in-ground power line was struck 4 - 6 ft away from where
these pc's were sitting. They have not since been able to be booted. I
bought two new motherboards (PC Chips M825G Mainboard Via KM266Pro;Sckt A;
462 (integrated video, audio, lan)), the ram, drives, and monitor check out
as working on working pc's. But nothing will display on the monitor when
used on these new MB's, the fans start, the drive lights flash, but nothing
displays. I have tried multiple power supplies, and several processors
(XP1600, XP1800, 2- XP2400, all AMD's). Online there are notes that the
bios reset jumper sometimes causes confusion on this model, but it turns off
all fans, etc. so I don't believe this is the problem. Does anyone know of
anything I may have missed? All power supplies tested with were in the house
at the time of the strike, is it possible 4 power supplies all failed in a
way that is allowing the fans and drives to power up, but not initialize the
monitor (I assume this would be no power to the processor)? Is the chipset
in the M825 picky when it comes to memory? The memory was tested on a PC
Chips M811, and a ASUS A7V8X-LA.
Thanks.

 

[w_tom]

Quite normal for fans to spin, lights glow, and computer not work. A
problem that could be power supply or could be other components of that
power supply 'system'.

Locating the problem is not about buying new parts - shotgunning. It
starts with two minutes and a multimeter. General description of what
to do and look for was described previously in:
"Computer doesnt start at all" in alt.comp.hardware on 10 Jan 2004
at
http://tinyurl.com/2t69q and
"I think my power supply is dead" in alt.comp.hardware on 5 Feb 2004
at
http://www.tinyurl.com/2musa

In your case, the first voltage measurement starts with the purple
(+5VSB) line that should always have power if plug connects to wall.
Minimum acceptable voltage would be 5.87. Then move on to green wire
that would be much greater than 2.0 volts when computer is off and less
than 0.8 volts when power switch is pressed.

Other wires of significance are gray, red, yellow, and orange.
Furthermore, the numbers - not just above minimum but how much above -
are so useful as to be posted here for further information. What
happens to red, yellow, and orange as power switch is pressed can
provide further insight.

Once the power supply 'system' is verified, only then do you move on
to other 'usual' suspects. All this to identify a suspect faster and
without complications (and expense) created by 'shotgunning'.

Meanwhile, a direct lightning strike causing damage to interior
electronics suggests either you don't have the 'whole house' protector
(essential for transistor protection) or your protection system is not
properly earthed. If building does not, at minimum, meet post 1990
National Electrical Code (NEC) requirements, then household electronics
have no effective protection. The most critical component of
transistor protection is single point earth ground - not a protector.
This much larger topic discussed elsewhere such as in
comp.dcom.cabling entitled "problem between power and communication
cable" on 10 Feb 2005 at
http://makeashorterlink.com/?V2D1134AA

Once you have established the computer's foundation - its power
supply system - is functional, only then are you ready to move on to
other 'suspects'. Multimeters are so essential, inexpensive, and
ubiquitous as to be sold even in Home Depot, Sears, Radio Shack, and
Lowes.

 

[who]

Thank you, for the information. I had been looking for a listing of what
wires should have what voltages. The pc's in question had components
literally blown off of the MotherBoard, and their replacement was obviously
necessary. In most previous occasions I have shotgunned. Mainly because in
the process of rebuilding old cheap computers from bunches of junk, I have
had nearly unlimited replacement parts, but very little time. In this case,
I really did need to have the values to check against my power supply. I
need to get out of the 'shotgun' mindset, as you put it. These pc parts are
more expensive.
The lightning strike struck the power line, but these pc's were not
connected to it, and therefore not grounded properly. (Following this event,
I reviewed the wiring, and found the ground wire at the breaker panel had
been nitched when the insulation was stripped, causing it to break when the
previous owner's electrical contractor bent it to connect it, so it was
broken off, but touching. Obviously of no use, but appeared at a quick
glance to be ok.) I do own a multimeter, but had been unable to find a
listing of what wires should have what readings, and therefore, it had been
of little use. I understand that there can be many causes for this
condition, but am looking for assistance in eliminating troubleshooting of
unnecessary components. I will follow your suggestions as soon as I get
home.
Thanks.
PS. I can't believe I overlooked the -64 in the newsgroup name. But, I was
in a hurry, and I am subscribed to this NG to see reviews and opinions.

 

[w_tom]

That post and other citations say nothing about grounding a PC.
Earthing of lightnnig must occur long before that transient gets to a
computer. Furthermore earthing must be less than 10 feet from each
utility to the common earthing electrode - no sharp bends, no splices,
and not inside metallic conduit. Earthing the breaker box (one
incoming AC electric wire) is not sufficient. AC electric has how many
wires? Other AC wires must also be earthed - via a 'whole house'
protector.

Why would components be damaged? Because lightning found a path to
earth ground via that computer. For example, was the mouse wire draped
behind the desk to as to touch baseboard heat? That could be an
outgoing connection to earth.

To have an electrical current, both an incoming and outgoing path
must exist. Without both, then no electricity flows through
components. Outgoing path is to earth when lightning is on an incoming
path. Learn how lightning got into and out of (both are necessary to
have electric current flow) damaged electronics. Use the dead body
(damaged electronics) to learn how lightning flowed (the circuit path
to earth) so that future failures are avoided.

Note some DC voltage may be provided in previous citations such as
4.75 minimum for 5 volts. But 5 volts must measure above 4.87; 12
volts (yellow) above 11.7; and 3.3 (orange) never below 3.22 volts.

 

[who]

What I meant by grounding was the fact that had these pc's received their
spike from the power lines, it most likely would have went to ground before
it got to them. You are correct that the broken wire would not have made any
difference in this situation, just a grumble as to the quality of electrical
contractors in this area, and an indication that although I have reviewed
the wiring, it is possible for there to be similar situations on ground
wires inside walls, etc. However, evidentally there was a path to these pc's
which carried enough power to fry the motherboard. They were not connected
to the power lines, in fact they had no wires connected to them. They were
sitting next to the wall in our office. This is so unlikely it is almost
laughable, if I was to venture a guess I would say that the strike travelled
through a nail in the wall to a screw in the sheetrock, through these two
pc's then out to the grounded workstation they were sitting against. The
only apparent damage in the case is several components blown off of the
lower right corner of the motherboard on one, and the center of the other,
at about the location of the case side cooling fan. The house we are
referring to is partially DC, partially AC, totally off grid - wind, and
solar, no power generation equipment was damaged by the strike, nothing else
in the house. Maybe I should have just said lightning struck just outside
the wall of the house, because the fact that it hit the power line does not
really matter.
The type of answer I was hoping for was if a bad processor would keep the mb
from energizing video, if the motherboard would report errors via flashes of
the drive lights, if bad memory would show up after post, therefore after
initializing video? Will the mb initialize video without drives connected?
What is the minimum that needs to be connected for the mb to initialize
video? Just a little help to eliminate certain parts before I start
thoroughly debugging components.
Again, Thanks for the help.

 

[w_tom]

If I remember correctly, your building was 1970s construction.
Therefore it requires that AC electric service probably be upgraded per
post 1990 earthing standards. If it only connects to a cold water pipe
(that is usually too far away), then it is earthed for human safety but
not sufficiently earthed for transistor safety. Your entire
neighborhood should consider this upgrade correction.

Simplest way (after confirming power supply system integrity) to
isolate defects would be to strip a system down to a minimal
configuration. That is motherboard, power supply, processor, and
speaker. No memory, peripherals, keyboard, mouse, video controller,
monitor etc. If a most basic function is working, then the BIOS will
look for memory, see none, and beep the speaker. If the speaker does
not beep, (and since the power supply system is known good from a
multimeter), then you have a short list of possible defects.

Processor is only one the last things to be damaged for a variety of
reasons that will not be listed. No speaker beep leaves a very short
list of suspects.

If speaker does beep, then add components. For example, keyboard and
mouse. Next add memory. Then add video controller and monitor. Slow
build a system of known good parts until something defective causes
speaker to not beep or video to not display BIOS message.

Those flashing lights tell us nothing useful. For example, the disk
drive is a complete and separate computer. Keyboard is also a separate
computer. Flashing disk drive or keyboard lights only mean that
computer did something. Did it do something good? We don't know.
Flashing lights, spinning fans, etc tell us little about whether a
system is working. They only suggest power is applied - even if the
voltage is too low.

 

[nos1eep]

It is further alleged that on or about Wed, 1 Mar 2006 10:36:45 -0600,
in alt.comp.hardware.amd.x86-64, the queezy keyboard of "who"
<[email protected]> spewed the following:

|The type of answer I was hoping for was if a bad processor would keep the mb
|from energizing video,
*yes*
| if the motherboard would report errors via flashes of
|the drive lights,
*no*
|if bad memory would show up after post,
*sometimes*
|therefore after initializing video?
*yes*
|Will the mb initialize video without drives connected?
*yes*
|What is the minimum that needs to be connected for the mb to initialize
|video?
*processor, RAM, graphics*
|Just a little help to eliminate certain parts before I start
|thoroughly debugging components.

 

[w_tom]

BIOS needs no DRAM to write to video's memory (create a video
display). However BIOS may halt and not attempt to write to video if
BIOS does not see some memory. Each motherboard will require only one
type of memory or be more flexible - multiple types of memory. Some
motherboards already have the minimum memory chip attached. Your
question must first provide information from manufacture datasheet.
But if the BIOS does not halt (and beep), then BIOS can write to video
card without using motherboard memory.

What will initialize processor, RAM, and graphics? Depends on which
initialization you are talking about. BIOS performs minimal
initialization of these. OS then replaces BIOS and reinitializes - more
comprehensively. BIOS only needs minimal RAM to get past the RAM
detection test.

Not to complicate things too much, the motherboard has this whole
other 'operating system' that, for example, detects and sets up the PCI
bus and other hardware. This also performs only using components
inside motherboard. That PCI, et al setup makes DOS look simple. And
yet most users don't even know that complex embedded program even
exists.

Most hardware that requires extensive initialization looks to you as
if is automatically powers up configured. I don't know who deep you
want to go into this, but the best way is to just perform the strip
down minimal testing as described earlier and ask questions with
details provided. There are no simple answers to your questions
because there are so many more 'ifs' and 'buts'.