Computer won't boot

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I was edited an AVI file I had captured but when I tried to save it to my
new Maxtor 160gb hard drive I got a blue screen. The only way I could get
rid of it was to turn off my computer. When I tried to restart it would not
reboot and the monitor would not come on. Fans run, hard drives run but 3
1/2 drive won't. Switch on front panel will only cut off computer if you
hold it down for a while. Any thoughts? Thanks
William
 
Any chance this file you captured was done with a cord attached to the video
card? It sounds as if the card may have come partly out of the socket. AGP
cards are bad about that, that's the reason then have hold down clips on
them.
 
Hey Wayne
Could have but since then I removed all cards and started putting them
back in starting with the video card. Still nothing. Thanks.
William
 
I don't know if anyone is still reading this post but I still can't get my
computer to boot. The fans run, the cd rom and the dvd rom drives start and
I belive I can feel the hard drives running. The light on the 3 1/2 floppy
stays on all the time. Monotor and the switch on the front of the computer
does not light and I hear no beep. I changed the power supply 2 weeks ago
and everything was fine until I got a blue screen and had to power down.
When I turned yhe computer back on my troubles started. If I unplug the
power supply from the computer can I still check the voltages? Any ideas and
help will be greatly appreciated.
William
 
On an ATX power supply, you'll have to know which pins to jumper in order to
turn it on and check the voltage. Either Belkin or Antec makes an adapter
the will aid with this. If you have another power supply you can try, just
disconnect the leads from the motherboard and connect the new power supply
to it and see if it will turn on. You don't need to mount it in the case to
try this. Don't forget that some P4 and Athalon boards have more than one
power connector from the power supply to the motherboard.

Without power to the peripherals (i.e. hard drive) it won't get far, but if
you get the BIOS boot screen, you've found your problem.
 
Swapping the power supply does not guarantee a good supply.
It is also why your car mechanic would be called a sham if he
used that shotgun repair method. Until numbers are obtained
using a 3.5 digit multimeter (the inexpensive solution) or
some more expensive equipment, then numerous strange problems
can occur.

Procedure to verify power with a multimeter takes but a few
minutes and is explained in "Computer doesnt start at all"
in alt.comp.hardware on 10 Jan 2004 or
http://tinyurl.com/2t69q

Chart cited in that procedure (that was once informative)
has since been 'improved'. Better chart is:
Voltage Wire Color Min V Max V
+5 V Red 4.75 V 5.25 V
-5 V White -4.75 V -5.25 V
+12 V Yellow 11.4 V 12.6 V
-12 V Blue -11.4 V -12.6 V
+3,3 V Orange 3.135V 3.465 V
+5VSB Purple 4.75 5.25
!Power On Green 0.8 2.0
Power OK Gray 2.4


Computer will not boot or will appear intermittent if the
Power Good signal does not maintain level. Again, only a 3.5
digit multimeter will provide sufficient information.

That constantly on diskette light suggests a BIOS problem.
If power supply voltages and signals are proper, only then are
we ready to take on BIOS execution.
 
Thanks for the information. I copied it all down. As soon as I get the meter
and do the tests I'll get back to you.
William
 
One quick question. Is a digital multimeter different from a 3.5 digit
multimeter? I ask at my local Radio Shack store and he didn't know what it
was. I haven't heard of a 3.5 digit multimeter either. Thanks.
William
 
One quick question. Is a digital multimeter different from a 3.5 digit
multimeter? I ask at my local Radio Shack store and he didn't know what it
was. I haven't heard of a 3.5 digit multimeter either. Thanks.
William
Click to expand...

"3.5 digit" simply means that it's display can show 3.5 digits... that
is the most common consumer-grade digital multimeter available.
Any/all of their multimeters can measure voltage AFAIK.

For simple testing of power supply voltage (if you have no futher use
for the meter) a Radio Shack meter is more expensive than you need,
many hardware stores, Sams, Wall-Mart, etc, may sell a ~$10 meter that
is accurate enough for this purpose.
 
I was edited an AVI file I had captured but when I tried to save it to my
new Maxtor 160gb hard drive I got a blue screen. The only way I could get
rid of it was to turn off my computer. When I tried to restart it would not
reboot and the monitor would not come on. Fans run, hard drives run but 3
1/2 drive won't. Switch on front panel will only cut off computer if you
hold it down for a while. Any thoughts? Thanks
William
Click to expand...

Disconnect all IDE cables and all power cords to all
drives...especially the floppy.

Boot.


Have a nice week...

Trent

If the cheese isn't yours...its Nacho cheese!
 
I could only find a 16 ohm 12 watt resistor in my junk box. Will that work
or do I have to have a 10 ohm 10 watt? I measured the voltages without the
resistor any way. Here they are.
_____________
3.35v orange | 11 1 | orange 3.35v
-12.32v blue | 12 2 | orange 3.35v
black | 13 3 | black
green | 14 4 | red 5.07v
black | 15 5 | black
black | 16 6 | red 5.07v
black | 17 7 | black
-5.03v white | 18 8 | gray 5.07v
5.07v red | 19 9 | purple 5.16v
5.07v red | 20 10 | yellow 12.29v
 
I'll try that. Thanks.
William
Trent© said:
Disconnect all IDE cables and all power cords to all
drives...especially the floppy.

Boot.


Have a nice week...

Trent

If the cheese isn't yours...its Nacho cheese!
Click to expand...
 
I don't understand why you are using resistors. Motherboard
load makes testing more reliable. In fact, without loads on
all power supply voltages, then meter is less likely to detect
a bad supply.

Don't waste time removing a power supply from the system to
test it just like we don't waste time swapping power supplies
to find a problem. If using resistor because of that cited
URL, well, then I confused you. Only value in that URL was
the voltage chart and background information as to what tells
a supply to power on. Computer makes a better test load which
is why one need not remove a power supply to verify its
integrity.

A supply that works with minimal load of a power resistor
can still fail when loaded greater by computer. Take those
measurements when computer is drawing most power such as
burning a CD.

Those voltages look high which is why I suspect they were
taken without the motherboard and peripheral load. Take
voltage readings from one wire of same color. All reds are
interconnected. Same for orange, and black.
 
I could only find a 16 ohm 12 watt resistor in my junk box. Will that work
or do I have to have a 10 ohm 10 watt? I measured the voltages without the
resistor any way. Here they are.
_____________
3.35v orange | 11 1 | orange 3.35v
-12.32v blue | 12 2 | orange 3.35v
black | 13 3 | black
green | 14 4 | red 5.07v
black | 15 5 | black
black | 16 6 | red 5.07v
black | 17 7 | black
-5.03v white | 18 8 | gray 5.07v
5.07v red | 19 9 | purple 5.16v
5.07v red | 20 10 | yellow 12.29v
Click to expand...

As w_tom mentioned, the best readings will be seen from leaving the
power supply connected, installed in the system. Hopefully your meter
has probes that can be (carefully) inserted into the backside of the
ATX connector while it's plugged into the motherboard, taking care not
to short anything.

As for initial readings, those look fair enough, what would be
expected from a properly working power supply but the readings with
the system assembled enough that it would POST, if working, are
needed.

Trent's suggestion to unplug the drives, particularly the one that you
reported wasn't working, is good advice. If none of this helps the
next step mind be to clear the CMOS, and examine the motherboard for
signs of damage, most often vented capacitors appear with bludging,
cracked, leaky or residue, though they could instead show no outward
signs of failure.

Occasionally I come across power supplies with failing 5VSB circuit
which a simply voltmeter will show at correct levels, but the filter
capacitor in the power supply has expired and (presumably) the
instable voltage causes a motherboard crash, making it more likely to
power up from complete disconect/reconnect of AC power, rather than
leaving system sitting with 5VSB power applied for any length of time.
The simple end-user solution to that is power supply replacement.
 
Yes, that's why I was going to use a resistor because the URL suggested it.
I thought it would take place of the motherboard load. I was a little
insecure taking measurements with the power supply attached to the
motherboard but I will give it a try.
William
 
I am a little insecure of testing with the power supply hooked to the
computer but I will give it a try and be carefull. I did disconnect the
power and the IDE lines from all drives but nothing changed. I wish to
mention I am 62 years old and wear bifocals making my eyes not the best
seeing into hard to get at places. I don't know if this means anything or
not but for about a week I keep hearing a occasional click similar to that
of a modem relay then my trouble started. I did replace the PS because when
I measured the voltage at the hard disk power connector I was not getting a
reading so I removed the PS and opened it up to find a burned component so I
do have a new power supply that I'm working with which worked fine until
trouble. Thanks.
William
 
I am a little insecure of testing with the power supply hooked to the
computer but I will give it a try and be carefull. I did disconnect the
power and the IDE lines from all drives but nothing changed. I wish to
mention I am 62 years old and wear bifocals making my eyes not the best
seeing into hard to get at places. I don't know if this means anything or
not but for about a week I keep hearing a occasional click similar to that
of a modem relay then my trouble started. I did replace the PS because when
I measured the voltage at the hard disk power connector I was not getting a
reading so I removed the PS and opened it up to find a burned component so I
do have a new power supply that I'm working with which worked fine until
trouble. Thanks.
William
Click to expand...

Since the system isn't working anyway, it might be easier to go ahead
and pull the motherboard if you think access is a problem.

Perhaps I overlooked it but saw no mention of the make/model of power
supply, nor description of the system. If the power supply is generic
there's a real possibility it has a problem. Starting with a dead
system it's harder to troubleshoot an inadequate, poor power supply
than a dead one.

Stripping the system down to only bare essentials leaves only a few
possibilities... power supply, motherboard, and far less likely,
memory or video (considering this was a working system and presuming
that no fan failure of CPU or video card had occurred). _IF_ you feel
comfortable assuming the power supply is still good then odds are it's
the motherboard, which after clearing the CMOS and visually checking,
can't be resolved, then replacement is the only recourse. When it's a
question of which part is bad and final determination can't be made
without substitute parts, it may be wise to purchase from someplace
with a good return policy.

I hate to suggest it, but whatever problem caused your previous power
supply to fail, might still be present and working against the current
power supply... conceivably it too might be near failing, if the
warranty on it is expired already you might open it (after disconnect
from AC for a few minutes) and examine it... of course leaving power
off the whole time.
 
I am a little insecure of testing with the power supply hooked to the
computer but I will give it a try and be carefull. I did disconnect the
power and the IDE lines from all drives but nothing changed. I wish to
mention I am 62 years old and wear bifocals making my eyes not the best
seeing into hard to get at places. I don't know if this means anything or
not but for about a week I keep hearing a occasional click similar to that
of a modem relay then my trouble started. I did replace the PS because when
I measured the voltage at the hard disk power connector I was not getting a
reading so I removed the PS and opened it up to find a burned component so I
do have a new power supply that I'm working with which worked fine until
trouble. Thanks.
William
Click to expand...

Patient to doctor...

'Doc, my hands hurting all the time'.

Patient to doctor...5 visits later...

'Doc, I don't know if this means anything or not, but my neighbor blew
my hand off with a shotgun...and right after that is when it started
hurting.'

NOW you tell us about the blown power supply!! lol

If the machine won't boot with everything disconnected, one (or
several or all) of the major components is probably blown. You need
to check it by replacing one at a time. I'd start with the mb.

Good luck.


Have a nice week...

Trent

If the cheese isn't yours...its Nacho cheese, man!
 
I apologize for not telling you about the other PS but after I replaced it
and my system worked fine for a couple weeks I thought it was just the PS. I
know it's unfair to you for me not giving all the information. I just don't
know what's important and what's not. Also I didn't want to make my post too
lenghty. I already removed the CMOS battery for 15 minutes to clear it but
no change. The new PS is an ANTECH 350 watt ATX 12 V. I have an AMD Athlon
computer system.The old PS was a SPI 250 watt. I have also just recently put
in a maxtor 160gb hard drive with a ATA133 card. Could that affect my IDE
lines and my BUS? I was trying to write to the new hard drive when I got the
Blue Screen. I think I included this in my first post. Here are the new
voltage readings. Not much change.

PS connected to motherboard and 2 hard drives
_____________
3.35v orange | 11 1 | orange 3.35v
-12.50v blue | 12 2 | orange 3.35v
black | 13 3 | black
00.02v green | 14 4 | red 5.07v
black | 15 5 | black
black | 16 6 | red 5.07v
black | 17 7 | black
-5.04v white | 18 8 | gray 5.07v
5.07v red | 19 9 | purple 5.14v
5.07v red | 20 10 | yellow 12.21v
---------------
If either of you think it will help I will be glad to send a post with all
the changes and events for the last two to three weeks that could have a
bearing on any advice you might give. I don't want to take up any more of
your time than is required. Thanks for all the help so far.
William
 
Here's the problem. All acceptable power supplies must
include overvoltage protection. That means a power supply
failure could not cause damage to rest of computer. However
your original supply appears to be a clone and therefore
probably did not include the required overvoltage protection.
That means the power supply failure could have caused
overstress to other computer parts.

Unfortunately you are now dealing with an intermittent. One
way to start is to run manufacturer's diagnostics. All good
computer suppliers provide diagnostics for free. To make
those diagnostics more effective on intermittents, the 'unit
under test' can be heated with a hair drier on high. That is
normal operating temperature for electronics. Any electronics
that works at 70 degree F but fails diagnostic at high drier
temperatures is defective - and probably reason for
intermittent.

The hair drier test is most effective on memory and video
controller chips.

Unfortunately, this is an intermittent. That means a
constant collecting of information - including Trent's 'remove
a part and test again' procedure.

Those voltages say the power supply is not reason for
failure. Move on to other suspects.

Blue Screen of Death? That means you had important and
useful numbers on that screen. Numbers that would help point
in the direction of failure. Also is this an NT type system
such as XP? Then what do system logs say? Power supply is no
longer on the list of suspects. System logs may be crying out
the name of that suspect.
 
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