Is XP accessing both CPU cores?

[Guest]

Pentium D 820, i945P, Windows XP Pro SP2, latest drivers, bios, etc...

Device manager detects and displays both cores as two physical processors...
but, Task Manager's performance tab only seems to be accessing one CPU - one
Usage history graph. Under view > CPU history - One Graph per CPU is checked
off and greyed out... most of the time. The latest version of CPU-Z can only
detect information from one core (selection menu greyed out)... etc.

So, is XP using both cores? In a P4 w/HT you would see two performance
graphs... is there something preventing me from using both cores ?

 

[Guest]

Try going to intel.com,downloads,chip sets,locate,download and install the
chip set installation utility.

 

[V Green]

Did you originally have a single core and
upgrade to a dual core?

If so, your HAL may be wrong...

 

[Guest]

V. Green,

No, actually, it is an entirely new system.... which I presently have
running fine with XP pro... it even detects two physical processors... but is
not allowing me to use them as two logical cpus... in task manager, cpu-z,
etc.
I even tried re-installing windows and forcing the HAL for a multiprocessor
ACPI system... but the system would hang every time on the first reboot until
I forced the HAL back to a Standard ACPI system. Thanks for your suggestion
though... I think you are close....
Some more details on the system:
Abit AL8 Mobo, 2x512MB Samsung DDR2 + 2x1024MB OCZ DDR2, Powercolor Radeon
X700 256MB GameFX series, 2X Maxtor 250GB SATA in Raid0, Ultra X-Connect 500W
PSU, A sony DVD burner... and some other DVD/CD-RW combo drive... I do not
think the case is a TAC (Thermally Advantaged Chassis)... it is a
Coolermaster Cavalier... in case that makes a difference.

Windows XP and all hardware have the latest updates and drivers.


Thanks to anyone that can help... this is really bugging me...

 

[V Green]

HT enabled in BIOS?

I know, not the same as actual dual-core,
but enabling it (if there) might have same effect...

 

[Guest]

Oh, an interesting note about the install...
Windows XP setup would hang until I went into the BIOS > PnP/PCI Config and
set 'Resources Controlled By:' to 'Manual', rather than the default 'Auto
(ESCD)'.

One thing I have not tried is leaving the default for this setting in the
bios and also forcing the Multiprocessor HAL in WinXP setup... but since the
system hung up on the first attempt... with brand new hard drives... I'm not
sure this would help. The multiprocessor HAL should have been detected...
right? since I've never installed any other CPU on this Mobo. Perhaps someone
out there could shed some light?

It does seem strange that I had to change the above mentioned bios
setting... but it was something recommended for a system hang in Xp setup,
and it worked... sort of... I have XP Pro... but maybe the PD 820 does not
allow user control over the two cores?? I am boggled.

 

[Guest]

No. The PD 820 is dual core but does not support HT, so it is not displayed
in the bios settings. The Bios Correctly identifies the CPU as a Pentium D
820, 2.8GhZ, and as 2 physical processors.

 

[V Green]

Setting the Resources to Manual may make
the BIOS non-ACPI compliant.

This may cause XP setup to install the
incorrect HAL, and other things.

Hassle your MB mgfr. for a BIOS fix.

 

[P Ruetz]

Pentium D 820, i945P, Windows XP Pro SP2, latest drivers, bios, etc...

Device manager detects and displays both cores as two physical
processors...
but, Task Manager's performance tab only seems to be accessing one CPU -
one
Usage history graph. Under view > CPU history - One Graph per CPU is
checked
off and greyed out... most of the time. The latest version of CPU-Z can
only
detect information from one core (selection menu greyed out)... etc.

So, is XP using both cores? In a P4 w/HT you would see two performance
graphs... is there something preventing me from using both cores ?

Task manager can display one graph for both CPU's or one graph per CPU. Go
to View/CPU History to change.

My Dell 9100 bios lets me disable the second core. However, I don't think
that is your problem given that two are showing up in the device manager.

The load should be 50% for a single job CPU intensive job if both cores are
enabled. If you see 100% load for a single job, then you are using only one
core.

Peter

 

[Guest]

Peter,
How do I enable/disable a core in the cpu?
One Graph per CPU is checked, and also greyed out. There are no other
options in this part of the menu. In fact, all options relating to the use of
the second core are greyed out in all programs.

 

[P Ruetz]

Peter,
How do I enable/disable a core in the cpu?
One Graph per CPU is checked, and also greyed out. There are no other
options in this part of the menu. In fact, all options relating to the use
of
the second core are greyed out in all programs.

Sorry, I missed that detail in your original post. It sounds like Windows
is partially recognizing the dual cores.

Did you go into the bios and make sure both cores are enabled. I'm not sure
exactly where the option is, but on my 9100, I think there is a Performance
section with that option. It was enabled by default. Even if it is
enabled, try disabling, saving and then reenabling and saving. That should
not do any good, but I have come across machines where somehow the CMOS is
corrupted (setup shows L2 cache enabled, but machine is very slow. I
disable and then reenable the L2 cache and poof!, the machine is back up to
speed).

At some point, you could also try deleting the CPU devices and letting them
be redetected. However, don't do this if you aren't comfortable mucking
with your system. You might also try loading the latest chipset drivers, if
any.

You could also try a Linux live CD (requires no install) to see if it
detects both cores or not.

A Windows repair install (you wont lose your data) might also help. But it
takes time and might have some side effects.

Peter

 

[someone]

Sorry, I missed that detail in your original post. It sounds like Windows
is partially recognizing the dual cores.

Did you go into the bios and make sure both cores are enabled. I'm not sure
exactly where the option is, but on my 9100, I think there is a Performance
section with that option. It was enabled by default. Even if it is
enabled, try disabling, saving and then reenabling and saving. That should
not do any good, but I have come across machines where somehow the CMOS is
corrupted (setup shows L2 cache enabled, but machine is very slow. I
disable and then reenable the L2 cache and poof!, the machine is back up to
speed).

Alas, no such options in my bios.

 

[P Ruetz]

Alas, no such options in my bios.

You can also try cpuz or everest to see if they detect both cores or not.
Both work on my machine.

http://www.cpuid.org/cpuz.php
http://www.lavalys.com/

Peter