CPU Core Voltage Too Low -> Crash?

Don,

The voltages for the various components (RAM, CPU and etc.) are =
controlled by voltage regulators on the motherboard. Granted, it could =
be a different component that is having issues, and causing a voltage =
drop across the entire system. It could also simply be the voltage =
regulator that supplies the CPU Core Voltage failing due to age. =20

Try removing all add-on cards, and anything but your primary hard disk =
(you will need to leave the video card in) and retest the system. If =
the voltage is normal, then add the hardware back one piece at a time =
until you see the voltage drop. If you still get the voltage =
difference, even with all extra hardware removed, then you're most =
likely looking at a motherboard replacement.

--=20
Doug Knox, MS-MVP Windows XP/ Windows Smart Display
Win 95/98/Me/XP Tweaks and Fixes
http://www.dougknox.com
--------------------------------
Per user Group Policy Restrictions for XP Home and XP Pro
http://www.dougknox.com/xp/utils/xp_securityconsole.htm
--------------------------------
Please reply only to the newsgroup so all may benefit.
Unsolicited e-mail is not answered.
=20
"Don Cohen" wrote in message =
...
Hi,
=20
This is a fresh thread based on what was learned in a separate thread
(Desperately Need Help - System Reboot/Crashes).
=20
The tentative conclusion in the other thread is that my crashes are =
being
caused by hardware, and not software. In that regard, I have =
installed and
run AIDA32 Enterprise System Information. Here is the relevant =
information:
=20
My primary problem is random, sporadic crashes to a BSOD, starting =
after
almost 2 years of relatively glitch-free running, and *not* following =
any
significant hardware or software changes:
=20
PAGE_FAULT_IN_NONPAGED_AREA
****STOP: 0x00000050 (0xB7874E5E, 0x00000000, 0xB7874E5E, 0x00000000)
=20
Full details on this problem and prior trouble-shooting can be found =
in the
other thread.
=20
Gateway 700XL, approximately 2 years old, XP Home, 1024 mb RAM
Intel Pentium 4A, 2.2 GHz (5.5x400), Northwood A80532 CPU chip
Intel D850MV (Maryville) Motherboard, i850 Chipset
Brand new Antec 430W TruPower PSU (replacing the prior Gateway 250W =
PSU, but
not fixing the crashes)
=20
AIDA32 shows the actual CPU Core Voltage for my system varying between =
1.43
and 1.45 Volts.
AIDA32 also has a section showing the CPU Physical Properties. Here =
it
indicates:
--Core Voltage 1.475V - 1.55V--
=20
Someone experiencing similar (but not identical) crashes as me found =
his CPU
Core Voltage to be the source of his problem, indicating his opinion =
that
voltage differences as small as 0.025V can be quite significant. If =
true,
then my CPU Core Voltage is out of the normal range.
=20
My questions:
=20
1. Is the difference between the apparent optimal range for Core =
Voltage and
my actual Core Voltage enough to explain these very random crashes? (I =
can
go a few minutes, a few hours, a few days between crashes).
=20
2. Is there any way to adjust this voltage? I have not yet found any =
BIOS
or motherboard jumper settings that might do this.
=20
3. If this is the source of the problem, do I replace the motherboard, =
or
the CPU? In other words, which hardware component is causing the low =
CPU
Core Voltage?
=20
Anybody that can offer some knowledgeable advice here? It will be =
very
greatly appreciated. I have been fighting this problem for several =
weeks
now, and consumed untold hours trouble-shooting.
=20
Thanks!
=20
Don
=20

CS wrote:
On Sat, 21 Feb 2004 19:11:11 -0500, "Don Cohen"
wrote:


Nothing like going crazy trying to track something like this down....

Boy, is that the truth. It has consumed an incredible amount of time and
mental energy.


From reading your posts and replies and what you've already done to
trouble shoot the problem, I believe it is very definitely a hardware
issue.

I appreciate the confirmation. That seems like the only logical conclusion,
but we all know how strange the truth can be at times...


I would suggest you not spend any more money on diagnostic programs or
the like. Of course a free one is always great to have. I'm not
sure I really trust AIDA32 to accurately monitor CPU voltages. The
best free application that I know of to do that is called "Motherboard
Monitor". You might wish to download and give it a try. Also, go to
the CPU makers web site and get the specs for your CPU. Both Intel
and AMD have spec sheets available which give the voltage and
temperature ranges for the CPUs they manufacture.

OK, I've downloaded and installed Motherboard Monitor. Definitely more
complex than AIDA32 to setup. But I think I have it now.

It shows Core Temp for CPU varying between 1.46V and 1.49V. I checked
Intel's site, found my chip (SL66S) and it shows the spec for Core Voltage
as 1.500V. So according to MbMonitor my core voltage is still on the low
side, but how significant this 0.1 to 0.4 volts is, I don't know.

NOT 0.1 - 0.4 volts, but 0.01 - 0.04 volts. And the DA converters that
MbMontior and AIDA32 are reading generally don't have that degree of accuracy.
Accuracy would something like 1.46V to 1.49V plus or minus 0.1V at best.

If you want some what accurate measurements, test with a digital multi-meter
at the ATX power connector. You cannot test the core voltage directly at that
connector, but the core voltage is derived from the +3.3 volt line. You'd need
special ($$$) equipment to accurately measure core voltage.




Regarding additional diagnostic programs - I'd rather not buy more as well,
but at this point, I still don't have an answer as to what hardware is
faulty, and what to replace...


You may indeed have a bad motherboard or at least an intermittent
failing component on the board. It may even be memory related. I
don't recall you saying you swapped out the memory modules? Also, go
into your CMOS setup program and make sure all the settings for memory
are within specs. (CAS, RAS, etc)

His Gateway motherboard is somewhat lacking in the bios configuration department.


I haven't done anything yet with the actual (4) memory modules. Memtest86
ran for over 13 hours/7passes, with no errors detected.

Your MB uses RDRAM which is used in pairs.
Call the modules A1,A2 and B1,B2.
Call the slots they are in 1,2,3 and 4.
Swap A1,A2 from slots 1,2 to slots 3,4
and B1,B2 from slots 3,4 to slots 1,2.

While you're swapping the sticks (especially if you or someone in your
household is a smoker!), use SOFT (not for #1 pencil or ink) eraser to
clean the contacts.

Re-run Memtest86. If Memtest finds an error, replace the appropriate ram
module(s). If no errors are found, run the computer normally to see if
cleaning the contacts has fixed the intermitant spontaneous reboots.


Bob

Hi Doug,

Thanks for the reply and advice.

I presume that you feel the voltage measurements are sufficiently accurate
with "Motherboard Monitor" and/or AIDA32 to conclude that the VCore is
genuinely lower than it should be?

And if so, you also feel this small but significant difference could be
creating the system instability?

I will go ahead and give your plan a try tomorrow, and report back.

Thanks much!

Best regards,

Don

"Doug Knox MS-MVP" wrote in message
...
Don,

The voltages for the various components (RAM, CPU and etc.) are controlled
by voltage regulators on the motherboard. Granted, it could be a different
component that is having issues, and causing a voltage drop across the
entire system. It could also simply be the voltage regulator that supplies
the CPU Core Voltage failing due to age.

Try removing all add-on cards, and anything but your primary hard disk (you
will need to leave the video card in) and retest the system. If the voltage
is normal, then add the hardware back one piece at a time until you see the
voltage drop. If you still get the voltage difference, even with all extra
hardware removed, then you're most likely looking at a motherboard
replacement.

--
Doug Knox, MS-MVP Windows XP/ Windows Smart Display
Win 95/98/Me/XP Tweaks and Fixes
http://www.dougknox.com
--------------------------------
Per user Group Policy Restrictions for XP Home and XP Pro
http://www.dougknox.com/xp/utils/xp_securityconsole.htm
--------------------------------
Please reply only to the newsgroup so all may benefit.
Unsolicited e-mail is not answered.

"Don Cohen" wrote in message
...
Hi,

This is a fresh thread based on what was learned in a separate thread
(Desperately Need Help - System Reboot/Crashes).

The tentative conclusion in the other thread is that my crashes are being
caused by hardware, and not software. In that regard, I have installed
and
run AIDA32 Enterprise System Information. Here is the relevant
information:

My primary problem is random, sporadic crashes to a BSOD, starting after
almost 2 years of relatively glitch-free running, and *not* following any
significant hardware or software changes:

PAGE_FAULT_IN_NONPAGED_AREA
****STOP: 0x00000050 (0xB7874E5E, 0x00000000, 0xB7874E5E, 0x00000000)

Full details on this problem and prior trouble-shooting can be found in
the
other thread.

Gateway 700XL, approximately 2 years old, XP Home, 1024 mb RAM
Intel Pentium 4A, 2.2 GHz (5.5x400), Northwood A80532 CPU chip
Intel D850MV (Maryville) Motherboard, i850 Chipset
Brand new Antec 430W TruPower PSU (replacing the prior Gateway 250W PSU,
but
not fixing the crashes)

AIDA32 shows the actual CPU Core Voltage for my system varying between
1.43
and 1.45 Volts.
AIDA32 also has a section showing the CPU Physical Properties. Here it
indicates:
--Core Voltage 1.475V - 1.55V--

Someone experiencing similar (but not identical) crashes as me found his
CPU
Core Voltage to be the source of his problem, indicating his opinion that
voltage differences as small as 0.025V can be quite significant. If true,
then my CPU Core Voltage is out of the normal range.

My questions:

1. Is the difference between the apparent optimal range for Core Voltage
and
my actual Core Voltage enough to explain these very random crashes? (I can
go a few minutes, a few hours, a few days between crashes).

2. Is there any way to adjust this voltage? I have not yet found any BIOS
or motherboard jumper settings that might do this.

3. If this is the source of the problem, do I replace the motherboard, or
the CPU? In other words, which hardware component is causing the low CPU
Core Voltage?

Anybody that can offer some knowledgeable advice here? It will be very
greatly appreciated. I have been fighting this problem for several weeks
now, and consumed untold hours trouble-shooting.

Thanks!

Don

Hi Bob,

NOT 0.1 - 0.4 volts, but 0.01 - 0.04 volts. And the DA converters that
MbMontior and AIDA32 are reading generally don't have that degree of
accuracy.
Accuracy would something like 1.46V to 1.49V plus or minus 0.1V at best.

If you want some what accurate measurements, test with a digital
multi-meter
at the ATX power connector. You cannot test the core voltage directly at
that
connector, but the core voltage is derived from the +3.3 volt line. You'd
need
special ($$$) equipment to accurately measure core voltage.

A bit beyond my capabilities at the moment ;-)

His Gateway motherboard is somewhat lacking in the bios configuration
department.

So I've found...

Your MB uses RDRAM which is used in pairs.
Call the modules A1,A2 and B1,B2.
Call the slots they are in 1,2,3 and 4.
Swap A1,A2 from slots 1,2 to slots 3,4
and B1,B2 from slots 3,4 to slots 1,2.

While you're swapping the sticks (especially if you or someone in your
household is a smoker!), use SOFT (not for #1 pencil or ink) eraser to
clean the contacts.

Re-run Memtest86. If Memtest finds an error, replace the appropriate ram
module(s). If no errors are found, run the computer normally to see if
cleaning the contacts has fixed the intermitant spontaneous reboots.

Will do.

Thanks!

Don

Sorry to but in on this fishing expedition but it seems to me the only
thing
common to all your events is the CD Rom you were using with the Windows
disk. Try unplugging it and see if problems continue. A long shot I know
but
cheap to try.


No problem - join the party!

I'll add this to the list of things to try tomorrow.

Hopefully I'll come up with the answer sooner or later!

Don

Your voltages seem to be right where they are suppose to be with the
processor that you have ,and well within the working variance of the
specifications. Researching your stop error seem to point toward system
ram , taking into account the problems that you have posted . Although this
common stop error could be masked by underlying causes. Try one stick at a
time , then replacing more with successful operation. I too believe the best
way to troubleshoot is to pull out all the nonessential hardware and
software and replace one at a time. Good Luck . Jym



"Don Cohen" wrote in message
...
Hi Doug,

Thanks for the reply and advice.

I presume that you feel the voltage measurements are sufficiently accurate
with "Motherboard Monitor" and/or AIDA32 to conclude that the VCore is
genuinely lower than it should be?

And if so, you also feel this small but significant difference could be
creating the system instability?

I will go ahead and give your plan a try tomorrow, and report back.

Thanks much!

Best regards,

Don

"Doug Knox MS-MVP" wrote in message
...
Don,

The voltages for the various components (RAM, CPU and etc.) are controlled
by voltage regulators on the motherboard. Granted, it could be a
different
component that is having issues, and causing a voltage drop across the
entire system. It could also simply be the voltage regulator that
supplies
the CPU Core Voltage failing due to age.

Try removing all add-on cards, and anything but your primary hard disk
(you
will need to leave the video card in) and retest the system. If the
voltage
is normal, then add the hardware back one piece at a time until you see
the
voltage drop. If you still get the voltage difference, even with all
extra
hardware removed, then you're most likely looking at a motherboard
replacement.

--
Doug Knox, MS-MVP Windows XP/ Windows Smart Display
Win 95/98/Me/XP Tweaks and Fixes
http://www.dougknox.com
--------------------------------
Per user Group Policy Restrictions for XP Home and XP Pro
http://www.dougknox.com/xp/utils/xp_securityconsole.htm
--------------------------------
Please reply only to the newsgroup so all may benefit.
Unsolicited e-mail is not answered.

"Don Cohen" wrote in message
...
Hi,

This is a fresh thread based on what was learned in a separate thread
(Desperately Need Help - System Reboot/Crashes).

The tentative conclusion in the other thread is that my crashes are
being
caused by hardware, and not software. In that regard, I have installed
and
run AIDA32 Enterprise System Information. Here is the relevant
information:

My primary problem is random, sporadic crashes to a BSOD, starting after
almost 2 years of relatively glitch-free running, and *not* following
any
significant hardware or software changes:

PAGE_FAULT_IN_NONPAGED_AREA
****STOP: 0x00000050 (0xB7874E5E, 0x00000000, 0xB7874E5E, 0x00000000)

Full details on this problem and prior trouble-shooting can be found in
the
other thread.

Gateway 700XL, approximately 2 years old, XP Home, 1024 mb RAM
Intel Pentium 4A, 2.2 GHz (5.5x400), Northwood A80532 CPU chip
Intel D850MV (Maryville) Motherboard, i850 Chipset
Brand new Antec 430W TruPower PSU (replacing the prior Gateway 250W PSU,
but
not fixing the crashes)

AIDA32 shows the actual CPU Core Voltage for my system varying between
1.43
and 1.45 Volts.
AIDA32 also has a section showing the CPU Physical Properties. Here it
indicates:
--Core Voltage 1.475V - 1.55V--

Someone experiencing similar (but not identical) crashes as me found his
CPU
Core Voltage to be the source of his problem, indicating his opinion
that
voltage differences as small as 0.025V can be quite significant. If
true,
then my CPU Core Voltage is out of the normal range.

My questions:

1. Is the difference between the apparent optimal range for Core Voltage
and
my actual Core Voltage enough to explain these very random crashes? (I
can
go a few minutes, a few hours, a few days between crashes).

2. Is there any way to adjust this voltage? I have not yet found any
BIOS
or motherboard jumper settings that might do this.

3. If this is the source of the problem, do I replace the motherboard,
or
the CPU? In other words, which hardware component is causing the low
CPU
Core Voltage?

Anybody that can offer some knowledgeable advice here? It will be very
greatly appreciated. I have been fighting this problem for several
weeks
now, and consumed untold hours trouble-shooting.

Thanks!

Don

Hi Jym,

Your voltages seem to be right where they are suppose to be with the
processor that you have ,and well within the working variance of the
specifications. Researching your stop error seem to point toward system
ram , taking into account the problems that you have posted . Although
this
common stop error could be masked by underlying causes. Try one stick at a
time , then replacing more with successful operation. I too believe the
best
way to troubleshoot is to pull out all the nonessential hardware and
software and replace one at a time. Good Luck . Jym

Thanks. I guess this is what I'll be doing for the next few days.....

Best regards,

Don

More or less complicated than diagnosis of a human patient? I'll vote for more
complicated because of the infinite complexity of Windows... Ben Myers

On Sat, 21 Feb 2004 22:53:51 -0500, "Don Cohen"
wrote:

Hi Jym,

Your voltages seem to be right where they are suppose to be with the
processor that you have ,and well within the working variance of the
specifications. Researching your stop error seem to point toward system
ram , taking into account the problems that you have posted . Although
this
common stop error could be masked by underlying causes. Try one stick at a
time , then replacing more with successful operation. I too believe the
best
way to troubleshoot is to pull out all the nonessential hardware and
software and replace one at a time. Good Luck . Jym

Thanks. I guess this is what I'll be doing for the next few days.....

Best regards,

Don