I was wondering if anyone can give me some advice on the maximum in
overclocking a P4 at 1700 mhz? I run it at over 1800 mhz now but I
wonder if there is some generally recognised limit before you damage
the thing?
--
Verger
"What are we in time going by"-- Mountain ( For Yasgur's Farm)
Verger wrote:
> Hi,
>
> I was wondering if anyone can give me some advice on the maximum in
> overclocking a P4 at 1700 mhz? I run it at over 1800 mhz now but I
> wonder if there is some generally recognised limit before you damage
> the thing?
>
Some processor families have had observable failure conditions.
Note that the entries in the cpudatabase are not always good for
the long term health of the processor. (And some entries in the
database are pure nonsense.) Each processor has a max Vcore listed
in the processor datasheet (which you can download), and some are
more sensitive than others to abusing that limit. For example,
a Tualatin (nominal 1.5V) would fry after about a month at 1.8V.
Some people have lost AthlonFX processors on S939, and the cause
is believed to be related to the difference between Vcore and Vdimm.
(Also, some Athlon64 processors display what seems to be electromigration
failure, a gradual loss of overclockability.) So when you start an
overclocking project, it is a good idea to review the available
results from other enthusiasts.
For the really hot processors, sometimes the limits can be
thermal (you can no longer cool the processor well enough
or you fry the Vcore regulator). For example, the Pentium D 805
draws a tremendous amount of power if you run it at 4GHz (a
couple hundred watts). Rather than the processor failing, it
might be the motherboard that dies first. Some D 805 projects
got so hot, they melted foam placed underneath the processor
board, in the Vcore regulator area, while doing overclocks
on a table.
For my overclock on the computer I'm typing this on, my results
were rather obvious. Part of the frequency versus voltage
curve was rather gradual, and then I reached a point where
I could raise Vcore right to the datasheet limit (a "wall" so to speak),
and it wouldn't go a single hertz faster. That made the decision
as to what the operating point should be, rather obvious. No
point in cooking the thing, using more Vcore than really helps.
Other processors will tempt you with a more gradual curve, making
it harder to decide how much is too much. To make your own curve,
increase the CPU clock in steps of 5MHz, and only increase Vcore
if you cannot reach some stability criterion (some amount of Prime95
torture test time). Plot the points on a piece of paper, to see
the trend line.
"Verger" <nomail@maildump.nl> wrote in message
news:hqe5539kb69ie54gl16utiji41ebfujfk9@4ax.com...
> Hi,
>
> I was wondering if anyone can give me some advice on the maximum in
> overclocking a P4 at 1700 mhz? I run it at over 1800 mhz now but I
> wonder if there is some generally recognised limit before you damage
> the thing?
>
No, not really. You just have to monitor the temps and keep them as low as
possible. For the early P4s, I think the maximum temps were around 70-75c
where the processor would begin the throttle back. Temps rarely ever have
caused a processor failure, but overvoltage (vcore) can and will. Optimal
temperatures for your CPU would be under 60-62c under maximum load. You will
have other problems such as not posting or not loading the OS long before
you can damage the processor. What I would do is to take it as high as you
can and still stay stable at stock vcore and as soon as you have an issue
raise the vcore slightly until it becomes stable. Do all this in VERY small
increments while watching your core temperature. Idle temperatures may vary
depending on room temps, case airflow and the particular CPU cooler you
have. I use a program called Core Temp by Arthur Lieberman to monitor temps
and Orthos to load the processor. Both can be found easily with a simple
Google search at several different sites. Not knowing how overclocking
friendly your motherboard is I can't tell if your memory can be separated
from your system bus. If it cannot, that might also limit your ability to
get the maximum OC. There are a lot of variables, especially with the early
P4s that I wouldn't know about with the limited information I have about
your entire system.
'Verger' wrote:
| I was wondering if anyone can give me some advice on the maximum in
| overclocking a P4 at 1700 mhz? I run it at over 1800 mhz now but I
| wonder if there is some generally recognised limit before you damage
| the thing?
_____
You don't say what Pentium 4 you have, but I'd guess that it is not a
'Northwood' Pentium 4. If you have a Pentium 4 1.6 GHz 'Northwood' (512
KByte L2 cache) you would have a good chance at overclocking it to 2.4 GHz.
The earlier 'Williamette' Pentium 4 (256 KByte L2 cache) with a 0.18 micron
feature size would not overclock by more than a few hundred MHz.
Intel CPUs since the early Pentiums have had an internal diode that would
shut the CPU down before the temperature reached a catastrophic level; in
practice, an overheating Pentium will just hang and cool off with no harm
done before the 'fail-safe' thermal diode activates. There is no creditible
evidence that ANY Pentium CPU has been destroyed by heat. On the other
hand, applying an excessively high CPU core voltage can instantly destroy
the CPU (a 10 % increase or less is a safe maximum, but 15% is moving toward
the danger zone. It is not the clock speed or heat that is dangerous, but
rather voltage.
Phil Weldon
"Verger" <nomail@maildump.nl> wrote in message
news:hqe5539kb69ie54gl16utiji41ebfujfk9@4ax.com...
| Hi,
|
|
|
| --
|
| Verger
|
| "What are we in time going by"-- Mountain ( For Yasgur's Farm)
Phil Weldon wrote:
> 'Verger' wrote:
> | I was wondering if anyone can give me some advice on the maximum in
> | overclocking a P4 at 1700 mhz? I run it at over 1800 mhz now but I
> | wonder if there is some generally recognised limit before you damage
> | the thing?
> _____
>
> You don't say what Pentium 4 you have, but I'd guess that it is not a
> 'Northwood' Pentium 4. If you have a Pentium 4 1.6 GHz 'Northwood' (512
> KByte L2 cache) you would have a good chance at overclocking it to 2.4 GHz.
> The earlier 'Williamette' Pentium 4 (256 KByte L2 cache) with a 0.18 micron
> feature size would not overclock by more than a few hundred MHz.
>
> Intel CPUs since the early Pentiums have had an internal diode that would
> shut the CPU down before the temperature reached a catastrophic level; in
> practice, an overheating Pentium will just hang and cool off with no harm
> done before the 'fail-safe' thermal diode activates. There is no creditible
> evidence that ANY Pentium CPU has been destroyed by heat. On the other
> hand, applying an excessively high CPU core voltage can instantly destroy
> the CPU (a 10 % increase or less is a safe maximum, but 15% is moving toward
> the danger zone. It is not the clock speed or heat that is dangerous, but
> rather voltage.
>
> Phil Weldon
>
That is a good point. All of the 1.7Ghz processors here are 0.18u, so that
leaves no doubt it is a Willemette.
There should be datasheets for both a 423 package and a 478 package.
What I was able to find, is something for 423, but the same
technology limits should exist for both packages.
The nominal listed there is 1.70V or 1.75V for that group of
processor, and absolute max is 2.1V. Looking at the VID table for
the processor, it only goes up to 1.85V. So your average motherboard
may have that as a Vcore limitation. Maybe the Vcore can only be
boosted to 1.85V. You'd have to check a BIOS screen or the manual, to
see if more volts than that are available.
On Tue, 22 May 2007 08:38:07 -0400, Paul <nospam@needed.com> sang the
following hymns:
>Verger wrote:
>> Hi,
>>
>> I was wondering if anyone can give me some advice on the maximum in
>> overclocking a P4 at 1700 mhz? I run it at over 1800 mhz now but I
>> wonder if there is some generally recognised limit before you damage
>> the thing?
>>
>
>You can look up processor overclocks here.
>
>http://www.cpudatabase.com/index.cfm?Action=search
>
>Some processor families have had observable failure conditions.
>Note that the entries in the cpudatabase are not always good for
>the long term health of the processor. (And some entries in the
>database are pure nonsense.) Each processor has a max Vcore listed
>in the processor datasheet (which you can download), and some are
>more sensitive than others to abusing that limit. For example,
>a Tualatin (nominal 1.5V) would fry after about a month at 1.8V.
>Some people have lost AthlonFX processors on S939, and the cause
>is believed to be related to the difference between Vcore and Vdimm.
>(Also, some Athlon64 processors display what seems to be electromigration
>failure, a gradual loss of overclockability.) So when you start an
>overclocking project, it is a good idea to review the available
>results from other enthusiasts.
>
>"Sudden Overclocked Northwood Death Syndrome"
>http://www.xbitlabs.com/news/cpu/display/news6375.html
>
>For the really hot processors, sometimes the limits can be
>thermal (you can no longer cool the processor well enough
>or you fry the Vcore regulator). For example, the Pentium D 805
>draws a tremendous amount of power if you run it at 4GHz (a
>couple hundred watts). Rather than the processor failing, it
>might be the motherboard that dies first. Some D 805 projects
>got so hot, they melted foam placed underneath the processor
>board, in the Vcore regulator area, while doing overclocks
>on a table.
>
>For my overclock on the computer I'm typing this on, my results
>were rather obvious. Part of the frequency versus voltage
>curve was rather gradual, and then I reached a point where
>I could raise Vcore right to the datasheet limit (a "wall" so to speak),
>and it wouldn't go a single hertz faster. That made the decision
>as to what the operating point should be, rather obvious. No
>point in cooking the thing, using more Vcore than really helps.
>Other processors will tempt you with a more gradual curve, making
>it harder to decide how much is too much. To make your own curve,
>increase the CPU clock in steps of 5MHz, and only increase Vcore
>if you cannot reach some stability criterion (some amount of Prime95
>torture test time). Plot the points on a piece of paper, to see
>the trend line.
>
> Paul
This is helpful stuff. Thanks a lot!
--
Verger
"What are we in time going by"-- Mountain ( For Yasgur's Farm)
On Tue, 22 May 2007 14:00:45 GMT, "Phil Weldon"
<not.disclosed@example.com> sang the following hymns:
>'Verger' wrote:
>| I was wondering if anyone can give me some advice on the maximum in
>| overclocking a P4 at 1700 mhz? I run it at over 1800 mhz now but I
>| wonder if there is some generally recognised limit before you damage
>| the thing?
>_____
>
>You don't say what Pentium 4 you have, but I'd guess that it is not a
>'Northwood' Pentium 4. If you have a Pentium 4 1.6 GHz 'Northwood' (512
>KByte L2 cache) you would have a good chance at overclocking it to 2.4 GHz.
>The earlier 'Williamette' Pentium 4 (256 KByte L2 cache) with a 0.18 micron
>feature size would not overclock by more than a few hundred MHz.
Hmm. This is something I stuggle with. How can I find out exactly what
processor I have? I bet there is some tool that can read out a
processor?
>
>Intel CPUs since the early Pentiums have had an internal diode that would
>shut the CPU down before the temperature reached a catastrophic level; in
>practice, an overheating Pentium will just hang and cool off with no harm
>done before the 'fail-safe' thermal diode activates. There is no creditible
>evidence that ANY Pentium CPU has been destroyed by heat. On the other
>hand, applying an excessively high CPU core voltage can instantly destroy
>the CPU (a 10 % increase or less is a safe maximum, but 15% is moving toward
>the danger zone. It is not the clock speed or heat that is dangerous, but
>rather voltage.
>
>Phil Weldon
I haven't done any voltage changes. I am scared. So I have only
increased incrementally the thing to 1840 Ghz so far. it works stable.
I noticed the increased speed using the PC. So I wondered how far to
take it without doing anything complicated.
My mobo is an Asus P5B-533-E.
>
>"Verger" <nomail@maildump.nl> wrote in message
>news:hqe5539kb69ie54gl16utiji41ebfujfk9@4ax.com.. .
>| Hi,
>|
>|
>|
>| --
>|
>| Verger
>|
>| "What are we in time going by"-- Mountain ( For Yasgur's Farm)
>
--
Verger
"What are we in time going by"-- Mountain ( For Yasgur's Farm)
On Tue, 22 May 2007 10:54:57 -0400, Paul <nospam@needed.com> sang the
following hymns:
>Phil Weldon wrote:
>> 'Verger' wrote:
>> | I was wondering if anyone can give me some advice on the maximum in
>> | overclocking a P4 at 1700 mhz? I run it at over 1800 mhz now but I
>> | wonder if there is some generally recognised limit before you damage
>> | the thing?
>> _____
>>
>> You don't say what Pentium 4 you have, but I'd guess that it is not a
>> 'Northwood' Pentium 4. If you have a Pentium 4 1.6 GHz 'Northwood' (512
>> KByte L2 cache) you would have a good chance at overclocking it to 2.4 GHz.
>> The earlier 'Williamette' Pentium 4 (256 KByte L2 cache) with a 0.18 micron
>> feature size would not overclock by more than a few hundred MHz.
>>
>> Intel CPUs since the early Pentiums have had an internal diode that would
>> shut the CPU down before the temperature reached a catastrophic level; in
>> practice, an overheating Pentium will just hang and cool off with no harm
>> done before the 'fail-safe' thermal diode activates. There is no creditible
>> evidence that ANY Pentium CPU has been destroyed by heat. On the other
>> hand, applying an excessively high CPU core voltage can instantly destroy
>> the CPU (a 10 % increase or less is a safe maximum, but 15% is moving toward
>> the danger zone. It is not the clock speed or heat that is dangerous, but
>> rather voltage.
>>
>> Phil Weldon
>>
>
>That is a good point. All of the 1.7Ghz processors here are 0.18u, so that
>leaves no doubt it is a Willemette.
>
>http://processorfinder.intel.com/List.aspx?ProcFam=483
>
>An example here, shows 1.75V nominal.
>
>http://processorfinder.intel.com/det...px?sSpec=SL6BD
>
>There should be datasheets for both a 423 package and a 478 package.
>What I was able to find, is something for 423, but the same
>technology limits should exist for both packages.
>
>http://download.intel.com/design/Pen...s/24919805.pdf
>
>The nominal listed there is 1.70V or 1.75V for that group of
>processor, and absolute max is 2.1V. Looking at the VID table for
>the processor, it only goes up to 1.85V. So your average motherboard
>may have that as a Vcore limitation. Maybe the Vcore can only be
>boosted to 1.85V. You'd have to check a BIOS screen or the manual, to
>see if more volts than that are available.
>
> Paul
Thanks a lot guys. I'll study your help and experiment a little more.
--
Verger
"What are we in time going by"-- Mountain ( For Yasgur's Farm)
> Hmm. This is something I stuggle with. How can I find out exactly what
> processor I have? I bet there is some tool that can read out a
> processor?
>
This is a lot easier than you think :-) Remove the heat sink, wipe off
the gunk, and read the scribbles written on the CPU heat spreader. There
is an alphanumeric string starting with an "S", called sSpec. Feed it in
the Intel processor finder (on their web pages) and it will tell you all
you need to know. At this phase you might as well write down everything
written on the heat spreader, in case you need some other info later.
Remember to add some more goo when re-installing the heat sink :-)
P4 1700 Max OC 
Linear Mode
