computer won't start - no sounds

  • Thread starter Thread starter joe
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J

joe

It is a dell E510. I know this isn't a dell forum but still the smartest
forum around and so here I am with this question. The dell was
not starting. I changed out the power supply and no luck. With
either ps, the green light on mobo is on.

I press start button and there is a yellow light that blinks inside just
behind the switch.

I have been working on this for weeks because after a day or two,
it will start fine.

What do you all think??

Right now it is in state where it will not start. I put the new ps in
again and still it won't start.
 
I found batt that I am sure is fairly new, and reset cmos jumper.
Reseated ram and video card.
At some point it tried to start and I got the following error code.

Error code
long beep, long pause, then three long beeps with short pauses between
them, then long pause and then two long beeps with only a short beep
between them. That is it. A total of 6 beeps.
 
joe said:
I found batt that I am sure is fairly new, and reset cmos jumper.
Reseated ram and video card.
At some point it tried to start and I got the following error code.

Error code
long beep, long pause, then three long beeps with short pauses between
them, then long pause and then two long beeps with only a short beep
between them. That is it. A total of 6 beeps.
Click to expand...

Beep codes are available in the upper right hand corner of this page.
Try to use the page that corresponds to the BIOS brand used with the board.
Phoenix uses more complicated codes than some of the others. If you don't know
what BIOS is used, either look for a label stuck to the BIOS chip on the
motherboard, or look at pictures of the BIOS screen in the user manual,
and see if there is branding information printed on one of the BIOS pictures.

http://www.bioscentral.com/beepcodes/phoenixbeep.htm

When dealing with bad hardware, try to remove portions of the hardware
to simplify the setup. Make careful note of where the connectors go, their
orientation and so on, so you can put them back correctly later.

For example, if you remove all the RAM from the motherboard, you should get
a "missing RAM" beep code. If you're still getting your complicated beep
code, then that would suggest a test that occurs before an attempt to use
the RAM, is failing.

Before adding or removing hardware from a computer, always unplug it. The
purpose of unplugging, is to ensure that +5VSB is not available to the
motherboard. On Asus motherboards, there is a green LED on the surface of
the motherboard, which glows to warn you that +5VSB is still present.
By unplugging the power cable, you can be sure that the power is not
present, so it'll be safe to remove things like the RAM.

Paul
 
I removed the video card. There was a plastic cover over the video
from the motherboard. I guess the video card was an option. I also
removed the modem card which won't be used anyway. Just to test
the beep codes, I removed both 256M memory sticks.

When I plug power back in, the green mobo light is on (that has always
worked), but when I press the power on switch, nothing happens. And
I have replaced the power supply several times. Right now, the ps that
came with it is in place.

So I am suspicious of the on switch. I am not familiar with this mobo
and don't know how to short the switch. It is hidden in the front panel
with no clear way of getting to it.

Any suggestions??
 
joe said:
I removed the video card. There was a plastic cover over the video
from the motherboard. I guess the video card was an option. I also
removed the modem card which won't be used anyway. Just to test
the beep codes, I removed both 256M memory sticks.

When I plug power back in, the green mobo light is on (that has always
worked), but when I press the power on switch, nothing happens. And
I have replaced the power supply several times. Right now, the ps that
came with it is in place.

So I am suspicious of the on switch. I am not familiar with this mobo
and don't know how to short the switch. It is hidden in the front panel
with no clear way of getting to it.

Any suggestions??
Click to expand...

Is there a cable coming from the front panel, to a "PANEL" header
on the motherboard ? (It might be a 2x4 header, but I don't see it in
the manual.)

http://support.dell.com/support/edocs/systems/dim5150/en/sm/techov1.htm

Perhaps there is a cable with a 1x2 connector on the end, that comes
from that power switch ? In an emergency, you should be able to swap
the reset and power cables, to the PANEL header, so that the reset switch
can be used as a power switch. Both switches are momentary contact
type switches, so they should be interchangeable. And the switches don't
have to be connected. For example, when debugging on my table, sometimes
I stick a screwdriver tip, between the two pins that would normally
go to the power switch, so the motherboard starts with just a quick
touch of the pins. (Only do this, if the motherboard is out in the
open and in plain view. You don't want to stab the wrong things with
your screwdriver. I'm only making this point, to emphasize that the
switch is momentary contact.)

The manual claims there are the infamous diagnostic LEDs on this
machine. Do you see anything matching this description ?

http://support.dell.com/support/edocs/systems/dim5150/en/sm/tshoot1.htm#wp1120147

Put one stick of RAM back (with the power off), and try the system again.

Paul
 
When I plug power back in, the green mobo light is on (that has always
worked), but when I press the power on switch, nothing happens.  And
I have replaced thepower supplyseveral times.  Right now, the ps that
came with it is in place.
Click to expand...

Better is to first see a problem before removing or replacing
things. That shotgunning can even result in an exponentially more
complex problem.

Power switch does not connect to the power supply. It connects to a
supply controller that in turn makes decisions whether or not to turn
on the power supply. Your suspicions about the power switch implied
you did not know this.

Paul suggested shorting those power switch pins with a screw driver.
But better is to see what is happening between the controller and
power supply. A multimeter (sold even in Kmart) measures DC voltage
on the green wire between power supply and motherboard both before and
when power switch is pressed. Voltage change says nothing useful.
Useful answer are VDC numbers both before and when the power switch is
pressed.

Same applies to the purple wire. That LED only says an AC power
cord is connected. Voltages can be completely defective and still
that LED would light. What are VDC numbers on the purple wire?

Same also applies to motherboard battery. Measure that battery
without removing it or anything else. If using the typical CR2032 coin
cell, then a voltage at 2.8 volts says the battery is ready for
replacement in the next few months. A much lower voltage (ie 2.4
volts) implies that may be the reason for failure. Again, see a
problem before replacing things. Also see a problem long before it
creates a failure (ie battery at 2.8 volts).

Paul recommended another example for finding a problem before
removing, replacing or reseating anything - beep codes. What is your
beep code reporting? Many Dells also have a four light system status
display. What did they report?

Of course, AC power cord is always removed before making any
changes. If not, then further damage could have resulted making your
problem even more complex. That motherboard LED warns that AC power
cord was not disconnected - says nothing about sufficient power.

There is zero reason to suspect the switch until basic facts have
been provided. If green wire voltages are OK both before and when
switch is pressed, then switch and many other items have been
exonerated. That simple measurement reports massive quantities of
useful facts - especially if you did not yet remove or replace
anything.
 
Paul said:
Is there a cable coming from the front panel, to a "PANEL" header
on the motherboard ? (It might be a 2x4 header, but I don't see it in
the manual.)

http://support.dell.com/support/edocs/systems/dim5150/en/sm/techov1.htm

Perhaps there is a cable with a 1x2 connector on the end, that comes
from that power switch ? In an emergency, you should be able to swap
the reset and power cables, to the PANEL header, so that the reset switch
can be used as a power switch. Both switches are momentary contact
type switches, so they should be interchangeable. And the switches don't
have to be connected. For example, when debugging on my table, sometimes
I stick a screwdriver tip, between the two pins that would normally
go to the power switch, so the motherboard starts with just a quick
touch of the pins. (Only do this, if the motherboard is out in the
open and in plain view. You don't want to stab the wrong things with
your screwdriver. I'm only making this point, to emphasize that the
switch is momentary contact.)

The manual claims there are the infamous diagnostic LEDs on this
machine. Do you see anything matching this description ?

http://support.dell.com/support/edocs/systems/dim5150/en/sm/tshoot1.htm#wp1120147

Put one stick of RAM back (with the power off), and try the system again.

Paul
Click to expand...

I meant to say there was no beep codes with everything removed. That means
the
power switch must not be working - right??

I tried one stick of ram and no sticks of ram - no beep codes. That surely
isn't right.
The only blinking lights are two yellow leds on front panel when I press the
power
switch on front of computer.

There is a ribbon cable from mobo to small circuit board that has front
panel usb's on
it and yellow led's. I have to figure out how to get to the power switch on
front panel.
It is not obvious how I get to it.
 
When I plug power back in, the green mobo light is on (that has always
worked), but when I press the power on switch, nothing happens. And
I have replaced thepower supplyseveral times. Right now, the ps that
came with it is in place.
Click to expand...

Better is to first see a problem before removing or replacing
things. That shotgunning can even result in an exponentially more
complex problem.

Power switch does not connect to the power supply. It connects to a
supply controller that in turn makes decisions whether or not to turn
on the power supply. Your suspicions about the power switch implied
you did not know this.

Paul suggested shorting those power switch pins with a screw driver.
But better is to see what is happening between the controller and
power supply. A multimeter (sold even in Kmart) measures DC voltage
on the green wire between power supply and motherboard both before and
when power switch is pressed. Voltage change says nothing useful.
Useful answer are VDC numbers both before and when the power switch is
pressed.

Same applies to the purple wire. That LED only says an AC power
cord is connected. Voltages can be completely defective and still
that LED would light. What are VDC numbers on the purple wire?

Same also applies to motherboard battery. Measure that battery
without removing it or anything else. If using the typical CR2032 coin
cell, then a voltage at 2.8 volts says the battery is ready for
replacement in the next few months. A much lower voltage (ie 2.4
volts) implies that may be the reason for failure. Again, see a
problem before replacing things. Also see a problem long before it
creates a failure (ie battery at 2.8 volts).

Paul recommended another example for finding a problem before
removing, replacing or reseating anything - beep codes. What is your
beep code reporting? Many Dells also have a four light system status
display. What did they report?

Of course, AC power cord is always removed before making any
changes. If not, then further damage could have resulted making your
problem even more complex. That motherboard LED warns that AC power
cord was not disconnected - says nothing about sufficient power.

There is zero reason to suspect the switch until basic facts have
been provided. If green wire voltages are OK both before and when
switch is pressed, then switch and many other items have been
exonerated. That simple measurement reports massive quantities of
useful facts - especially if you did not yet remove or replace
anything.I need to cut the green wire to measure the voltage - right? I need to find
my voltmeter. It is not where it should be.

In the meantime, I do not understand why I don't always get a beep code.
That implies to me that the power switch on front is not working - I realize
it
may not be the switch itself but could be the circuit on the mobo or
something
in between. But if the mobo were getting power, wouldn't I hear some beep
codes when I remove everything???
 
joe said:
In the meantime, I do not understand why I don't always get a beep code.
That implies to me that the power switch on front is not working - I realize
it
may not be the switch itself but could be the circuit on the mobo or
something
in between. But if the mobo were getting power, wouldn't I hear some beep
codes when I remove everything???
Click to expand...

It may not apply to all motherboards, but the ones I know about,
rely on the execution of CPU code to cause the beeps. The CPU
can execute code, even when the RAM is missing. (As long as
the code uses CPU registers to hold intermediate results. And
it is possible to write code that way.)

If the cooling fans are spinning, when you press the power
button, that means the power supply has responded. A lack
of beeps at that point, means there could be a problem
elsewhere, like motherboard or CPU. Or, a power supply
voltage could be out of spec. Or the power_good signal
from the power supply did not get asserted. (Power_good,
and associated logic tree, prevents things from starting
until the power is determined to be stable. So even
if in fact, all voltages are proper and stable, a
failure to send power_good can stop it from beeping
or POSTing. Things like the motherboard Vcore circuit,
may contribute a status signal, to the power_good
logic.) Even a stuck reset switch, can prevent beeps
or POSTing.

I was hoping, if there were diagnostic LEDs, that they would
help. They're almost as effective as a Port 80 POST
status card.

Paul
 
Paul said:
If the cooling fans are spinning, when you press the power
button, that means the power supply has responded.
Click to expand...

The cooling fans are not spinning. Nothing happens except
the yellow led's flash.
 
joe said:
The cooling fans are not spinning. Nothing happens except
the yellow led's flash.
Click to expand...

The fans run off +12V, and the yellow LEDs could be on a
+5V rail. It would be pretty strange for only a part of
the power supply to fail, as they do share a certain amount
of common circuitry.

There is a sample power supply schematic here. The common output
transformer supplies power to more than one rail, and there are
few components after that, that could affect the power. Of course,
the motherboard could short out an output, but then the power
supply would likely shut off in seconds, due to the
overheating.

http://www.pavouk.org/hw/en_atxps.html

According to the Dell manual on their web page, item #8 in this
picture, is supposed to be four diagnostic LEDs. They may have
a pattern on them, indicating the failure type. If the CPU is
not able to execute BIOS code, then the lights cannot be updated
under program control. Normally, if there was a problem during
POST, and the BIOS code found a problem, then you could look up
the light pattern on the web page.

http://support.dell.com/support/edocs/systems/dim5150/en/sm/techov1a.jpg

Paul
 
In the meantime, I do not understand why I don't always get a beep code.
That implies to me that the power switch on front is not working - I realize
it may not be the switch itself but could be the circuit on the mobo or
something in between. But if the mobo were getting power, wouldn't I
hear some beep codes when I remove everything???
Click to expand...

Your question can only result in speculation. With numbers from the
power supply wires and numbers from the battery, then this post could
have answered these and previous questions AND probably identified the
suspect. A useful reply exists only if you provide those relevant
facts.

Do not cut a green wire. Don't remove anything. Don't replace
anything. As posted:
Better is to first see a problem before removing or
replacing things. and
That simple measurement reports massive quantities
of useful facts - especially if you did not yet remove
or replace anything.
Click to expand...

What was your beep code reporting (from provided web site)?
Irrelevant if beeps only happen sometimes. Relevant is what the beeps
actually reported. What do those four diagnostic lights report? What
are functions of two front panel yellow lights (what does the manual
call them) and what is their flash pattern (in numbers)?

Forget the switch for now. Anything about that switch already was
provided. Nothing new will be provided until important facts are
posted.

Paul has explained how relevant functions work. Better appreciate
what he has posted by providing the requested facts and numbers.
Significance of requested information will remain completely unknown
until after posted. Then irrelevance of a power switch or spinning
fan will be appreciated. To understand a computer has two separate
power supplies and other posts from Paul, provide results from all
those recommendations. Anything that can be known from observations
and speculations was provided in first posts. To learn more, collect
and post those requested facts without knowing why.

The point of every paragraph in this post. Your replies will only be
as useful as information provided. Your help is being starved of
anything that would result in a useful reply. Requested information
has near zero significance until resulting replies occur. Do those
diagnostic lights ever glow? Is CMOS battery voltage measured without
even removing the battery? Your replies will only be useful if you
provide the many requested facts and numbers.
 
Paul said:
It may not apply to all motherboards, but the ones I know about,
rely on the execution of CPU code to cause the beeps. The CPU
can execute code, even when the RAM is missing. (As long as
the code uses CPU registers to hold intermediate results. And
it is possible to write code that way.)

If the cooling fans are spinning, when you press the power
button, that means the power supply has responded. A lack
of beeps at that point, means there could be a problem
elsewhere, like motherboard or CPU. Or, a power supply
voltage could be out of spec. Or the power_good signal
from the power supply did not get asserted. (Power_good,
and associated logic tree, prevents things from starting
until the power is determined to be stable. So even
if in fact, all voltages are proper and stable, a
failure to send power_good can stop it from beeping
or POSTing. Things like the motherboard Vcore circuit,
may contribute a status signal, to the power_good
logic.) Even a stuck reset switch, can prevent beeps
or POSTing.

I was hoping, if there were diagnostic LEDs, that they would
help. They're almost as effective as a Port 80 POST
status card.

Paul
Click to expand...

I just got in from the weekend and tried again. Once again I get the beep
code
mentioned previously and now I am getting two green lights. There are a
total of
6 lights, 3 on the left side and 3 on the right. Of the 3 on each side, the
middle
light of each is about 1/2 inch higher on the front panel. If you number
the lights
1-6 left to right, only 4 and 5 are solid green. None of the others are
lit. The lights
stay green even though there is no POST or any indication that the video is
working.
The screen is dark and the power light is yellow (on the monitor screen
power switch).

Last time, the diagnostic lights did not go green. They just flashed yellow
although I
didn't notice which ones flashed. Until you mentioned that there were
multiple lights, I
did not notice that. You have to take off the dark plastic front piece to
see the individual
lights.
 
joe said:
I just got in from the weekend and tried again. Once again I get the beep
code
mentioned previously and now I am getting two green lights. There are a
total of
6 lights, 3 on the left side and 3 on the right. Of the 3 on each side, the
middle
light of each is about 1/2 inch higher on the front panel. If you number
the lights
1-6 left to right, only 4 and 5 are solid green. None of the others are
lit. The lights
stay green even though there is no POST or any indication that the video is
working.
The screen is dark and the power light is yellow (on the monitor screen
power switch).

Last time, the diagnostic lights did not go green. They just flashed yellow
although I
didn't notice which ones flashed. Until you mentioned that there were
multiple lights, I
did not notice that. You have to take off the dark plastic front piece to
see the individual
lights.
Click to expand...

Do the best you can, to compare the green LEDs, to the diagnostic LED web
page I posted. For example, maybe it matches the third code down, memory
failure.

http://support.dell.com/support/edocs/systems/dim5150/en/sm/tshoot1.htm#wp1120147

Paul
 
I put it all back together, and gave it one more try. This time it
started.

It has done this before. The computer will run and run but if I cut it off,
it might not start again. It has been doing this for months. However, this
most recent time I have had the most trouble getting it to start up. I
thought
for sure the power supply was faulty but obviously, that is not the problem.

I still don't know what the problem might be.
 
I just got in from the weekend and tried again. Once again I get the
beep code mentioned previously and now I am getting two green
lights. There are a total of 6 lights, 3 on the left side and 3 on the
right. Of the 3 on each side, the middle light of each is about 1/2
inch higher on the front panel.
Click to expand...

How did you know a power supply was defective? How do you know a
new power supply is good? You did not and you do not. Wild
speculation does not identify any defect and is not sufficient to
replace any part. Furthermore, a defective supply can boot a
computer. A perfectly good supply can fail in some computers. If you
did not take voltage measurements, no numbers means you know nothing
about either power supply.

Nobody is going to tell you what those beep codes report. Those
beeps are reporting facts that were provided. What exactly does the
beep code complain about? You must compare those beep codes to error
messaged in the charts.

It is a Dell. It has diagnostic lights. Meaning of those lights
were provided in Dell documentation AND in a URL provided by Paul.
Nobody is going to do what only you can do best. Compare those charts
to your lights. Report error messages for beep codes, for diagnostic
lights, and what those voltages are.

It is a Dell. It comes with comprehensive diagnostics - provide
free on a CD-Rom, in a diagnostic partition on the hard drive, and
from Dell's web site. Comprehensive hardware diagnostics are for
solving your problem. What did diagnostics report? But again, you
must do the work and report back.

Information from each paragraph, if provided, means the very next
post answers your question. Getting you to perform such simple tasks
has become more difficult than pulling teeth. Until you do these
simple things (without knowing why), then you will never solve the
problem. That computer is not the problem. You are. You are not
doing what works for an immediate solution.

Rather than waste time describing light locations, instead, you have
the chart. Read it. What do diagnostic lights report? What is that
beep code error message? What are those power supply voltages? What
do comprehensive hardware diagnostics report?

Stop entertaining emotions or psychic suggestions. No reason exists
to suspect the power switch. Time was wasted (maybe making the
problem worse) by replacing the power supply. Posters have described
how to 'follow the evidence'. Stop with the wild speculation. Post
answers to every sentence in that above paragraph to obtain a
solution.
 
Take your meds Tom and chill.


w_tom said:
How did you know a power supply was defective? How do you know a
new power supply is good? You did not and you do not. Wild
speculation does not identify any defect and is not sufficient to
replace any part. Furthermore, a defective supply can boot a
computer. A perfectly good supply can fail in some computers. If you
did not take voltage measurements, no numbers means you know nothing
about either power supply.

Nobody is going to tell you what those beep codes report. Those
beeps are reporting facts that were provided. What exactly does the
beep code complain about? You must compare those beep codes to error
messaged in the charts.

It is a Dell. It has diagnostic lights. Meaning of those lights
were provided in Dell documentation AND in a URL provided by Paul.
Nobody is going to do what only you can do best. Compare those charts
to your lights. Report error messages for beep codes, for diagnostic
lights, and what those voltages are.

It is a Dell. It comes with comprehensive diagnostics - provide
free on a CD-Rom, in a diagnostic partition on the hard drive, and
from Dell's web site. Comprehensive hardware diagnostics are for
solving your problem. What did diagnostics report? But again, you
must do the work and report back.

Information from each paragraph, if provided, means the very next
post answers your question. Getting you to perform such simple tasks
has become more difficult than pulling teeth. Until you do these
simple things (without knowing why), then you will never solve the
problem. That computer is not the problem. You are. You are not
doing what works for an immediate solution.

Rather than waste time describing light locations, instead, you have
the chart. Read it. What do diagnostic lights report? What is that
beep code error message? What are those power supply voltages? What
do comprehensive hardware diagnostics report?

Stop entertaining emotions or psychic suggestions. No reason exists
to suspect the power switch. Time was wasted (maybe making the
problem worse) by replacing the power supply. Posters have described
how to 'follow the evidence'. Stop with the wild speculation. Post
answers to every sentence in that above paragraph to obtain a
solution.
Click to expand...
 
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