Power loss shutdown staying down?

[drb]

Came home to find my clocks blinking and computer idling (nothing on the
screen but fans running. Turned computer power off and restarted after 15
seconds with no startup but fans running and no beeps. Pulled power plug and
recycled start up with still no running. Pulled power of one hard drive and
has a flash. Left power cables off both hard drives, floppy and CDROM with
still no startup. Any suggestions?

Was thinking maybe the cmos is messed up or would there be a fuse that can
be replaced?

 

[Val]

Before you pulle the power from the drives, did you see any flashing of
drive activity light?

Maybe problem is with video card or monitor?

Was everything on a decent surge protector?

 

[Efirmitiv]

My other computer has the similar problem, when starting up after reading
the bios specs and 5 sec after it shuts down. I think it's because i had
erased all of system logs etc. so this files are empty. I am not into system
functioninig but i suppose its the reason why it shuts down!?

 

[drb]

Had a surge protector but nothing special about it. Replaced video card with
old one. Still no startup not even able to get into bios. Turn monitor off
and still no startup. Any fuse to check?

 

[drb]

Not similar to my problem since I can even get it to start into bios.

Any other suggestions?

 

[Val]

Sounds like something blew when the power came back. Sometime when power is
restored it surges and bounces bit.

Next thing to get checked is the Power Supply, it seems to be delivering 12V
for the fans, what about the 5V lines?

Motherboard?

Looks like a trip to the repair shop, if the machine is worth it.

Val

 

[drb]

CDROM light comes on and draw opens. Is that a 5v line going there?

 

[w_tom]

CDROM light comes on and draw opens. Is that a 5v line going there?

Without results that provide numbers, then everything will be
nothing more than wild speculation. For example:

Sounds like something blew when the power came back.
Sometime when power is restored it surges and bounces bit.

When power comes back on, due to so many things being powered
simultaneously, then voltage remains low and slowly rises up. This is
the best type of power up to electronics. In fact, electronics often
contain a device to create this slow voltage rise. However people
without electrical knowledge assume voltage surges high when first
powered on only due to feelings. Do they first learn facts? No.
They hear that power surges when first turned on. They assume 'surge'
means high voltage. The resulting current surge means no excessive
voltage; great power-on for electronics and poor power-on for electric
motors.

If damage was created with power loss, then damage was more likely
created before power went off. Again, another example of others who
somehow know only using feelings.

Back to the original problem. Lights can illuminate; fans can spin;
and voltage is still too low. Everything inside that computer is
'unknown'. Solution begins by placing various parts of a computer,
one sub-system at a time, into either the 'definitely good' or
'definitely bad' category. Notice the ternary conditions: good, bad,
and unknown.

A tool sold even where screwdrivers are sold (even K-mart) is
required. This 3.5 digit multimeter provides numbers in but two
minutes. Voltage numbers are taken on any one of orange, red, purple,
and yellow wires (from power supply to motherboard) both 'before'
power button is pressed and 'when' power button is pressed. Those
numbers must exceed 3.23, 4.87, and 11.7. Even an Ipod is more
complex. Some pictures demonstrating where that measurement is taken
are
http://techrepublic.com.com/5102-10586-5566528.html
http://www.helpwithpcs.com/courses/power-supply-basics-inc-pinouts.htm

Your replies will only be as useful as numbers and facts provided.
Power supply 'system' (more than just a power supply) is the
foundation of a computer. Everything can appear defective if those
above numbers are not in spec. Nobody can provide a useful answer
without those numbers. Power supply 'system' is the first system to
take from "unknown' to either 'definitely good' or 'definitely bad'
state. Only if that subsystem is 'definitely good', then we move on
to other suspects.

Notice you don't disconnect anything since too many changes may only
exponentially complicate the problem. Shotgunning is another bad
diagnostic procedure.

If surge protector was adjacent to computer, then it may have
contributed to computer damage. Again, many somehow know when hearing
the word 'surge protector' and then assume that means 'surge
protection'. Those are two different items. But again, an example of
people 'feeling' rather than first learning.

Use two minutes and that 3.5 digit multimeter to obtain numbers.
Posting those numbers here will result in replies from people with
technical knowledge. How complex is that meter? So complex as to be
sold in Home Depot, Radio Shack, Wal-mart, Tru-Value Hardware, and K-
mart for about $20. A tool as necessary as a screwdriver.

 

[drb]

Hooked a dc pocket meter to hard drive power cable black+red=5v and
black+yellow=12v. Same thing true with connector to motherboard as well as
black+orange=5v. Also connected another power supply to motherboard and got
same results with no startup with fans running.

For a couple restarts the lights flashed on the keyboard. After taking out
the 2 sticks of ram and putting 1 in at a time the lights no longer come on.
Odd?

Also disconnected everything (HD, cdrom, floppy) and no change. Changed the
video card with no effect. What else can I do or test?

 

[w_tom]

Hooked a dc pocket meter to hard drive power cable black+red=5v and
black+yellow=12v. Same thing true with connector to motherboard as well as
black+orange=5v. Also connected another power supply to motherboard and got
same results with no startup with fans running.

For a couple restarts the lights flashed on the keyboard. After taking out
the 2 sticks of ram and putting 1 in at a time the lights no longer come on.
Odd?

Changing things without first identifying the problem is called
shotgunning. IOW you may have just exponentially complicated the
original problem.

Using a pocket meter, what was the purple wire voltage before power
switch was pressed? What was the purple wire voltage when power
switch was pressed? What was the orange wire voltage before power
switch was pressed? What was the voltage as power switch is pressed?
The previous post asked for each number during each action. Your
replies will only be as useful as numbers and facts provided.

Of course that pocket meter must be 3.5 digits minimum.

So what were those numbers for each wire before and when power
switch is pressed? Is every number zero? Is one at 0.65 volts?
That's not zero. Every number is significant information that may
mean nothing to you. Another reason why numbers are collected - so
that others with fundamental knowledge can identify things not so
obvious. Post every number - and do not shotgun the problem.

 

[Leythos]

Of course that pocket meter must be 3.5 digits minimum.

Bull crap, even an old analog meter would work to test the power supply
output on any current computer.

If the OP were to disconnect the devices, install a cheap PSU, we could
have this narrowed down to the parts that your testing with a DVM won't
show as faulty or not.

--

Leythos
- Igitur qui desiderat pacem, praeparet bellum.
- Calling an illegal alien an "undocumented worker" is like calling a
drug dealer an "unlicensed pharmacist"
(e-mail address removed) (remove 999 for proper email address)

 

[drb]

Thanks for the down to earth clarification. It prompted me to check out the
CPU after I hooked up another power supply with no success.

Put my CPU into another computer and found it not working. Don't know how to
test the Soyo Dragon Lite motherboard so probably will have to take it in or
probably cheaper replace both and get later hardware. I assume that if a
processor blows from a surge the motherboard went with it, right?

Thanks everyone for giving me your input. I did learn a few things.

 

[w_tom]

Thanks for the down to earth clarification. It prompted me to check out the
CPU after I hooked up another power supply with no success.

Put my CPU into another computer and found it not working. Don't know how to
test the Soyo Dragon Lite motherboard so probably will have to take it in or
probably cheaper replace both and get later hardware. I assume that if a
processor blows from a surge the motherboard went with it, right?

Thanks everyone for giving me your input. I did learn a few things.








- Show quoted text -

 

[w_tom]

Surges typically do not damage CPUs. With an incoming path and no
outgoing path, no electrical circuit (for a surge) exists through the
CPU. No incoming and outgoing path means no surge damage.

CPUs are rarely damaged. But CPUs may be harmed by a short list of
suspects including internal manufacturing defects, excessive
temperature (AMD types only), and excessive voltage. CPUs have their
own dedicated power supply that is controlled by the CPU. Just
another reason why surges don't harm CPUs. To have excessive
voltage, that 'motherboard resident' power supply would have to fail.
Install another CPU, and it too might be damaged by motherboard power
supply.

Other reasons for CPU failure also exist (far less likely) including
some reasons created by removing and installing CPU. CPUs are one of
the most robust components on a motherboard. It is rare to have CPU
failure without something else - typically on motherboard - creating
that failure. Some of these failures can occur during normal
operation; don't appear until later when power cycling occurs.

If you really do have a CPU failure, it is probably best not to put
a new CPU is what is now an unknown motherboard. However CPU failures
are so rare that you might want to reevaluate your test in the other
motherboard - whether that other motherboard really supports that
unique CPU.

 

[Leythos]

Thanks for the down to earth clarification. It prompted me to check out the
CPU after I hooked up another power supply with no success.

Put my CPU into another computer and found it not working. Don't know how to
test the Soyo Dragon Lite motherboard so probably will have to take it in or
probably cheaper replace both and get later hardware. I assume that if a
processor blows from a surge the motherboard went with it, right?

Thanks everyone for giving me your input. I did learn a few things.

Unless the CPU was designed for the motherboard you installed it in,
well, there was little hope that it would actually work. Soyo is not
exactly a quality board vendor, so there could be many problems.

I've seen surges fry everything on a motherboard, RAM, CPU, CAPS, etc...

In all my years, 30+, I've only seen a handful of CPU's go bad, but I've
seen a ton of motherboards and improperly jumpered CPU settings (making
it look like a bad CPU).

With nothing connected except Video, PSU and CPU you should get a POST
of some type - or at least a series of beeps, with RAM added you should
see it count the memory.

You should also reset the BIOS to factory defaults and CPU detection to
automatic if the board has it.

What CPU do you have for this?

--

Leythos
- Igitur qui desiderat pacem, praeparet bellum.
- Calling an illegal alien an "undocumented worker" is like calling a
drug dealer an "unlicensed pharmacist"
(e-mail address removed) (remove 999 for proper email address)