PC has no video and no beep code??

  • Thread starter Thread starter Roy Mottola
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R

Roy Mottola

This is a windows machine, P4, Asus P4C800ED board. Machine worked
flawlessly for years, suddenly lost video. Hard drive lights and fans stayed
on. When attempting to reboot, fans come on but no beep code. My question:
What are all the possible reasons for why the machine won't beep, other than
bad case speaker or speaker connection.

Thanks, Roy
 
This is a windows machine, P4, Asus P4C800ED board. Machine worked
flawlessly for years, suddenly lost video. Hard drive lights and fans
stayed on. When attempting to reboot, fans come on but no beep code. My
question: What are all the possible reasons for why the machine won't
beep, other than bad case speaker or speaker connection.
Click to expand...

So many causes are possible that you need a structured
list of tests (in rational order) as published in a few repair
manuals. I use and recommend PC Help Desk in a Book (Que.)
 
Roy said:
This is a windows machine, P4, Asus P4C800ED board. Machine worked
flawlessly for years, suddenly lost video. Hard drive lights and fans stayed
on. When attempting to reboot, fans come on but no beep code. My question:
What are all the possible reasons for why the machine won't beep, other than
bad case speaker or speaker connection.
Click to expand...

The video BIOS has to load before the system BIOS (which would generate
the beep code). That's so you can actually use the system BIOS, like to
view its config screens. If the video BIOS doesn't load then the
subsequent load of the system BIOS won't happen.

A bad video card or controller won't affect voltages to the hard disks
and fans. Did you open the case to check that the fan for the video
card is spinning?

Got another video card to use for testing?

Does the motherboard have onboard video? If so, are you using it or did
you install a video card? If you have a video card and onboard video
then test by removing the video card and use the onboard video.
 
VanguardLH said:
The video BIOS has to load before the system BIOS (which would generate
the beep code). That's so you can actually use the system BIOS, like to
view its config screens. If the video BIOS doesn't load then the
subsequent load of the system BIOS won't happen.

A bad video card or controller won't affect voltages to the hard disks
and fans. Did you open the case to check that the fan for the video
card is spinning?

Got another video card to use for testing?

Does the motherboard have onboard video? If so, are you using it or did
you install a video card? If you have a video card and onboard video
then test by removing the video card and use the onboard video.
Click to expand...

That makes sense. Is the video bios part of the card, or part of the
motherboard?
The first thing I did was swap the video card, with same results.
Systematically, I disconnected everything not essential right down to
removing the board to isolate it from possible mounting short circuit
issues.
 
Don Phillipson said:
So many causes are possible that you need a structured
list of tests (in rational order) as published in a few repair
manuals. I use and recommend PC Help Desk in a Book (Que.)

--
Don Phillipson
Carlsbad Springs
(Ottawa, Canada)
Thanks, it's too bad there isn't a more recent incarnation of the book, but
I ordered a copy anyway
Click to expand...
 
Roy said:
This is a windows machine, P4, Asus P4C800ED board. Machine worked
flawlessly for years, suddenly lost video. Hard drive lights and fans stayed
on. When attempting to reboot, fans come on but no beep code. My question:
What are all the possible reasons for why the machine won't beep, other than
bad case speaker or speaker connection.

Thanks, Roy
Click to expand...

Check your ICH5R Southbridge for burn marks.

http://onfinite.com/libraries/179057/2ea.jpg

Whenever an ICH5/ICH5R machine fails to do much of anything,
start by assuming a "latchup failure" on the USB subsystem. That
causes a large current to flow between the power input points
of the USB pads on the Southbridge chip. If the bond wires hold
up while the current is flowing, the top of the ICH5/ICH5R is
burned as shown.

Perhaps the last thing you did, was plug a USB device into the
(relatively floating) USB port on the front of the computer ? Using
the rear USB ports on an ICH5/ICH5R motherboard may extend the life,
but at least a few posters with this problem, didn't have a
clearly associated ESD (electrostatic discharge) event correlating
with boot failure.

When a latchup failure occurs, a heavy current flows until the power
source is disabled, and the rail voltage drops to zero. Latchup
failure forms a PNPN junction, otherwise known as an SCR. If a user
was immediately aware latchup had occurred, they'd have a second or
two to remove power. And this information is of no real use in the
real world, because you're not hyper-tuned to expecting it, and
even if you were, you might still not make it in time to stop it.
It's like a "melt down". For most users, a minute or two pass, before
the realization it's broken.

My P4C800-E Deluxe still works, but is a backup machine now. I never wired
the front USB ports, and haven't used USB too much on it (mainly because
I didn't have a lot of USB stuff to begin with).

If you had a lot of add-in PCI cards, you could strip the machine down
a bit, and remove excess hardware, and check for different symptoms.
You could also attempt a "beep test", by removing all memory sticks
and the AGP video card, forcing the computer to "beep an error code".
If it doesn't beep, then you're getting closer to concluding the
processor simply cannot execute code any more. A burned Southbridge
prevents access to the bytes of code stored in the BIOS EEPROM. To
"beep", you really need a working Northbridge, hub bus, Southbridge,
and interface to the EEPROM, to suck in bytes of code. A burned
Southbridge stops that. A missing ATX12V power cable would give
similar symptoms (try re-plugging it).

Paul
 
Paul said:
Check your ICH5R Southbridge for burn marks.

http://onfinite.com/libraries/179057/2ea.jpg

Whenever an ICH5/ICH5R machine fails to do much of anything,
start by assuming a "latchup failure" on the USB subsystem. That
causes a large current to flow between the power input points
of the USB pads on the Southbridge chip. If the bond wires hold
up while the current is flowing, the top of the ICH5/ICH5R is
burned as shown.

Perhaps the last thing you did, was plug a USB device into the
(relatively floating) USB port on the front of the computer ? Using
the rear USB ports on an ICH5/ICH5R motherboard may extend the life,
but at least a few posters with this problem, didn't have a
clearly associated ESD (electrostatic discharge) event correlating
with boot failure.

When a latchup failure occurs, a heavy current flows until the power
source is disabled, and the rail voltage drops to zero. Latchup
failure forms a PNPN junction, otherwise known as an SCR. If a user
was immediately aware latchup had occurred, they'd have a second or
two to remove power. And this information is of no real use in the
real world, because you're not hyper-tuned to expecting it, and
even if you were, you might still not make it in time to stop it.
It's like a "melt down". For most users, a minute or two pass, before
the realization it's broken.

My P4C800-E Deluxe still works, but is a backup machine now. I never wired
the front USB ports, and haven't used USB too much on it (mainly because
I didn't have a lot of USB stuff to begin with).

If you had a lot of add-in PCI cards, you could strip the machine down
a bit, and remove excess hardware, and check for different symptoms.
You could also attempt a "beep test", by removing all memory sticks
and the AGP video card, forcing the computer to "beep an error code".
If it doesn't beep, then you're getting closer to concluding the
processor simply cannot execute code any more. A burned Southbridge
prevents access to the bytes of code stored in the BIOS EEPROM. To
"beep", you really need a working Northbridge, hub bus, Southbridge,
and interface to the EEPROM, to suck in bytes of code. A burned
Southbridge stops that. A missing ATX12V power cable would give
similar symptoms (try re-plugging it).

Paul
Click to expand...

Thanks Paul,
The southbridge chip looks fine, as does the entire board. I was curious if
some voltage issue with the power supply could cause a no beep situation,
but one of the first things I did was plug in another power supply, and got
no change. The machine was running at the time of failure, just sitting on a
web page when the screen went black. I hadn't recently plugged in any USB
devices, although a number of USB devices are permanently connected. Mouse,
keyboard, card reader, bluetooth, and maybe something else I'm missing. I
tried booting without a video card, and with a different video card, no
change. I pulled the 4 sticks of ram as well, and tried booting with just
one stick, then swapped sticks, still no beeps
 
RBM said:
Thanks Paul,
The southbridge chip looks fine, as does the entire board. I was curious if
some voltage issue with the power supply could cause a no beep situation,
but one of the first things I did was plug in another power supply, and got
no change. The machine was running at the time of failure, just sitting on a
web page when the screen went black. I hadn't recently plugged in any USB
devices, although a number of USB devices are permanently connected. Mouse,
keyboard, card reader, bluetooth, and maybe something else I'm missing. I
tried booting without a video card, and with a different video card, no
change. I pulled the 4 sticks of ram as well, and tried booting with just
one stick, then swapped sticks, still no beeps
Click to expand...

Your next check, would be to inspect capacitors for leaking or bulging.
Perhaps Vcore converter is toast due to bad caps ? (Vcore runs off ATX12V power.)
The tops of the caps are supposed to be flat. The "lines" stamped
in the top of an electrolytic, are for pressure relief, so the
pressure is relieved before it becomes too great.

http://www.badcaps.net/images/caps/kt7/image004.png

http://www.badcaps.net/images/caps/ka7/ka7_0149.jpg

Also, you can find rust colored or orange goo. If the "rubber bung"
at the bottom of the capacitor pushes out (causing the cap to tilt
off vertical), there can also be orange goo on the PCB. If left long
enough, the orange goo can attack metals in the area.

http://upload.wikimedia.org/wikipedia/commons/1/1e/Blown_up_electrolytic_capacitor.jpg

When a capacitor fails short circuit, there can be collateral damage to
toroidal coils or to MOSFETs. Stuff gets burned by the power supply
when that happens. That's why, you should replace the capacitors when
they are visibly compromised, as it's much harder to find exact replacements
for burned MOSFETs or toroidal coils, than for the electrolytic capacitors
themselves.

*******

My money however, is still on the Southbridge. If you had capacitors issues, you'd
be telling us about the BSODs you were getting, days before the final failure.
When a board just "dies", that smells more like a Southbridge. Just out of the blue
so to speak. Speaking of "smell", try sniffing around the chip, and see if there
is any smell to speak of.

Paul
 
Paul said:
Your next check, would be to inspect capacitors for leaking or bulging.
Perhaps Vcore converter is toast due to bad caps ? (Vcore runs off ATX12V
power.)
The tops of the caps are supposed to be flat. The "lines" stamped
in the top of an electrolytic, are for pressure relief, so the
pressure is relieved before it becomes too great.

http://www.badcaps.net/images/caps/kt7/image004.png

http://www.badcaps.net/images/caps/ka7/ka7_0149.jpg

Also, you can find rust colored or orange goo. If the "rubber bung"
at the bottom of the capacitor pushes out (causing the cap to tilt
off vertical), there can also be orange goo on the PCB. If left long
enough, the orange goo can attack metals in the area.

http://upload.wikimedia.org/wikipedia/commons/1/1e/Blown_up_electrolytic_capacitor.jpg

When a capacitor fails short circuit, there can be collateral damage to
toroidal coils or to MOSFETs. Stuff gets burned by the power supply
when that happens. That's why, you should replace the capacitors when
they are visibly compromised, as it's much harder to find exact
replacements
for burned MOSFETs or toroidal coils, than for the electrolytic capacitors
themselves.

*******

My money however, is still on the Southbridge. If you had capacitors
issues, you'd
be telling us about the BSODs you were getting, days before the final
failure.
When a board just "dies", that smells more like a Southbridge. Just out of
the blue
so to speak. Speaking of "smell", try sniffing around the chip, and see if
there
is any smell to speak of.

Paul
Click to expand...

The caps, like everything else that's visible, look perfect. My son had a
P5AD2E board, where the caps went bad, which was pretty obvious. I will say,
the southbridge looks darker in it's center, but is perfectly flat with no
obvious burns. No smell at all, either
 
RBM said:
The caps, like everything else that's visible, look perfect. My son had a
P5AD2E board, where the caps went bad, which was pretty obvious. I will say,
the southbridge looks darker in it's center, but is perfectly flat with no
obvious burns. No smell at all, either
Click to expand...

Do you run the processor at stock, or with boosted Vcore ? Northwood has
"instant death syndrome" at a certain magic voltage, if you use too much.

Paul
 
Paul said:
Do you run the processor at stock, or with boosted Vcore ? Northwood has
"instant death syndrome" at a certain magic voltage, if you use too much.

Paul
Click to expand...

I don't overclock anything. I do have an aftermarket copper cooler, but I
also dropped in another CPU, just to rule that out
 
RBM said:
I don't overclock anything. I do have an aftermarket copper cooler, but I
also dropped in another CPU, just to rule that out
Click to expand...

I think you said you have a P4C800-E Deluxe but I'm not sure.

If you had a P4C800 Deluxe, there was an issue with a solder blob, underneath
the plastic retention frame. Too much pressure from the heatsink attachment,
causes the blob to short out. Only the first batch was affected, as they
eventually figured it out. This is what happens, when you get lazy, and
bolt on the plastic thing, before running the PCB through the soldering equipment.

http://web.archive.org/web/20040227200251/http://koti.mbnet.fi/~nightops/eki/DSC00249.JPG

http://www.techsupportforum.com/forums/f15/asus-p4c800-deluxe-problems-and-solutions-6104-3.html (post #45)

The P4C800-E Deluxe came later, and I don't think it had the same problem.

Paul
 
RBM said:
The first thing I did was swap the video card, with same results.
Systematically, I disconnected everything not essential right down to
removing the board to isolate it from possible mounting short circuit
issues.
Click to expand...

Does the monitor say "no signal"?
 
Paul said:
I think you said you have a P4C800-E Deluxe but I'm not sure.

If you had a P4C800 Deluxe, there was an issue with a solder blob,
underneath
the plastic retention frame. Too much pressure from the heatsink
attachment,
causes the blob to short out. Only the first batch was affected, as they
eventually figured it out. This is what happens, when you get lazy, and
bolt on the plastic thing, before running the PCB through the soldering
equipment.

http://web.archive.org/web/20040227200251/http://koti.mbnet.fi/~nightops/eki/DSC00249.JPG

http://www.techsupportforum.com/forums/f15/asus-p4c800-deluxe-problems-and-solutions-6104-3.html
(post #45)

The P4C800-E Deluxe came later, and I don't think it had the same problem.

Paul
Click to expand...

It's an "E" deluxe
 
You said the hard disks spin and the fans will spin when you power up.
Have you actually looked inside to verify this? If so, did you check
the heatsink is still attached to the CPU and its fan is spinning?
 
VanguardLH said:
You said the hard disks spin and the fans will spin when you power up.
Have you actually looked inside to verify this? If so, did you check
the heatsink is still attached to the CPU and its fan is spinning?
Click to expand...

I'm not sure about the hard drives. I believe the hard drive light was on
when the screen went black. All the fans work, including the cpu cooler. I
replaced the cpu, just to verify it, with no change
 
RBM said:
I'm not sure about the hard drives. I believe the hard drive light was on
when the screen went black. All the fans work, including the cpu cooler. I
replaced the cpu, just to verify it, with no change
Click to expand...

So *do* the hard disks spin up when you power up?
 
VanguardLH said:
So *do* the hard disks spin up when you power up?
Click to expand...

I'm not sure. With the noise of the fans it wasn't obvious. Since I wasn't
even getting a beep code, I was looking for something at a lower level. At
this point the machine is totally stripped down
 
I don't recall seeing if you have already checked the *loaded* voltages
from the PSU. With the PSU connected to the motherboard, possibly the
video card (if it has a 12V connector), at least one hard disk (the one
with the OS partition), are the voltages on the 12V and 5V lines within
specs when you check with a multimeter?
 
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