«

Hyperthreading is turned OFF in the bios. When should it be ON? My x64 PC
has 2 processors.

Chuck

Yes, Hyperthreading is supported under x64, it should show up under Task
Manager as two processors.

Check out the following link which tells you about Hyperthreading, its
purpose and how to set it up:
http://www.intel.com/support/process.../CS-017371.htm
--
Andre
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"Chuck Goldstein" <> wrote in message
news:09KdncjRm9ICcUbfRVn-...
> Hyperthreading is turned OFF in the bios. When should it be ON? My x64
> PC has 2 processors.
>
> Chuck
>

"Chuck Goldstein" <> wrote in message
news:09KdncjRm9ICcUbfRVn-...
> Hyperthreading is turned OFF in the bios. When should it be ON? My x64
> PC has 2 processors.
>

It should be ON in the BIOS when you want to enable the hyper threading on
your two processors,
Doing so will then display 4 CPUs in Task Manager.

--

Regards,

Mike
--
Mike Brannigan [Microsoft]

This posting is provided "AS IS" with no warranties, and confers no
rights

Please note I cannot respond to e-mailed questions, please use these
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"Chuck Goldstein" <> wrote in message
news:09KdncjRm9ICcUbfRVn-...
> Hyperthreading is turned OFF in the bios. When should it be ON? My x64
> PC has 2 processors.
>
> Chuck
>

If you turn it on in BIOS, you'll see an apparent 4 processors. But before
you do that, think about the workload your machine does. Would it really
benefit from 4 processors over 2? Certainly few if any workstations need or
would use 4 processors. Two? yes, definitely, and I turn on HT on my single
proc workstations. But there is overhead in the # of processors, and
hyperthreading is NOT the same as actually having a dual core processor. So I
would almost certainly not turn on HT for an actual dual processor machine.
On a server, now, that's a different question and depends on the workload.

--
Please, all replies to the newsgroup.
======================
Charlie.
http://www.msmvps.com/xperts64/


Chuck Goldstein wrote:
> Hyperthreading is turned OFF in the bios. When should it be ON? My
> x64 PC has 2 processors.
>
> Chuck

"Charlie Russel - MVP" <> wrote in message
news:...
> If you turn it on in BIOS, you'll see an apparent 4 processors. But before
> you do that, think about the workload your machine does. Would it really
> benefit from 4 processors over 2? Certainly few if any workstations need
> or would use 4 processors. Two? yes, definitely, and I turn on HT on my
> single proc workstations. But there is overhead in the # of processors,
> and hyperthreading is NOT the same as actually having a dual core
> processor. So I would almost certainly not turn on HT for an actual dual
> processor machine. On a server, now, that's a different question and
> depends on the workload.


Charlie,

The "overhead" in managing multiple CPUs is far outweighed by the additional
processing capability provided (obviously only up to a certain number of
CPUs), so in the case of workstation class machines (single or dual
socketed) I would certainly turn on HT for both CPUs.
Obviously this is an extremely high level view and generalisation as yes
workload can impact the potential performance gains for a HT system, but
under "normal" applications and work patterns most "average" users might as
well get the benefit from the CPUs they have purchased and use HT if
available.

--

Regards,

Mike
--
Mike Brannigan [Microsoft]

This posting is provided "AS IS" with no warranties, and confers no
rights

Please note I cannot respond to e-mailed questions, please use these
newsgroups

"Charlie Russel - MVP" <> wrote in message
news:...
> If you turn it on in BIOS, you'll see an apparent 4 processors. But before
> you do that, think about the workload your machine does. Would it really
> benefit from 4 processors over 2? Certainly few if any workstations need
> or would use 4 processors. Two? yes, definitely, and I turn on HT on my
> single proc workstations. But there is overhead in the # of processors,
> and hyperthreading is NOT the same as actually having a dual core
> processor. So I would almost certainly not turn on HT for an actual dual
> processor machine. On a server, now, that's a different question and
> depends on the workload.
>
> --
> Please, all replies to the newsgroup.
> ======================
> Charlie.
> http://www.msmvps.com/xperts64/
>
>
> Chuck Goldstein wrote:
>> Hyperthreading is turned OFF in the bios. When should it be ON? My
>> x64 PC has 2 processors.
>>
>> Chuck
>
>

I agree with you, Mike. I am using a dual Xeon EM64T workstation. Two
processors without HT are far better than one for 3D rendering (almost twice
as fast, actually). But with HT turned on for both processors, 3D rendering
is still 15-20% faster, which is not negligible, IMO.

"Mike Brannigan [MSFT]" <> wrote in message
news:eZIU7$...
> "Charlie Russel - MVP" <> wrote in message
> news:...
>> If you turn it on in BIOS, you'll see an apparent 4 processors. But
>> before you do that, think about the workload your machine does. Would it
>> really benefit from 4 processors over 2? Certainly few if any
>> workstations need or would use 4 processors. Two? yes, definitely, and I
>> turn on HT on my single proc workstations. But there is overhead in the #
>> of processors, and hyperthreading is NOT the same as actually having a
>> dual core processor. So I would almost certainly not turn on HT for an
>> actual dual processor machine. On a server, now, that's a different
>> question and depends on the workload.
>
>
> Charlie,
>
> The "overhead" in managing multiple CPUs is far outweighed by the
> additional processing capability provided (obviously only up to a certain
> number of CPUs), so in the case of workstation class machines (single or
> dual socketed) I would certainly turn on HT for both CPUs.
> Obviously this is an extremely high level view and generalisation as yes
> workload can impact the potential performance gains for a HT system, but
> under "normal" applications and work patterns most "average" users might
> as well get the benefit from the CPUs they have purchased and use HT if
> available.
>
> --
>
> Regards,
>
> Mike
> --
> Mike Brannigan [Microsoft]
>
> This posting is provided "AS IS" with no warranties, and confers no
> rights
>
> Please note I cannot respond to e-mailed questions, please use these
> newsgroups
>
> "Charlie Russel - MVP" <> wrote in message
> news:...
>> If you turn it on in BIOS, you'll see an apparent 4 processors. But
>> before you do that, think about the workload your machine does. Would it
>> really benefit from 4 processors over 2? Certainly few if any
>> workstations need or would use 4 processors. Two? yes, definitely, and I
>> turn on HT on my single proc workstations. But there is overhead in the #
>> of processors, and hyperthreading is NOT the same as actually having a
>> dual core processor. So I would almost certainly not turn on HT for an
>> actual dual processor machine. On a server, now, that's a different
>> question and depends on the workload.
>>
>> --
>> Please, all replies to the newsgroup.
>> ======================
>> Charlie.
>> http://www.msmvps.com/xperts64/
>>
>>
>> Chuck Goldstein wrote:
>>> Hyperthreading is turned OFF in the bios. When should it be ON? My
>>> x64 PC has 2 processors.
>>>
>>> Chuck
>>
>>
>
>

Interesting, Mike. I don't have a dual proc machine that also supports
hyperthreading, so I certainly can't directly test this. But I am surprised
that you think that a "normal" user (which on this group would definitely
mean a power user) would see much benefit beyond two full procs. Guess I'm
just going to have to afford some better machines.

--
Please, all replies to the newsgroup.
======================
Charlie.
http://www.msmvps.com/xperts64/


Mike Brannigan [MSFT] wrote:
> "Charlie Russel - MVP" <> wrote in
> message news:...
>> If you turn it on in BIOS, you'll see an apparent 4 processors. But
>> before you do that, think about the workload your machine does.
>> Would it really benefit from 4 processors over 2? Certainly few if
>> any workstations need or would use 4 processors. Two? yes,
>> definitely, and I turn on HT on my single proc workstations. But
>> there is overhead in the # of processors, and hyperthreading is NOT
>> the same as actually having a dual core processor. So I would almost
>> certainly not turn on HT for an actual dual processor machine. On a
>> server, now, that's a different question and depends on the workload.
>
>
> Charlie,
>
> The "overhead" in managing multiple CPUs is far outweighed by the
> additional processing capability provided (obviously only up to a
> certain number of CPUs), so in the case of workstation class
> machines (single or dual socketed) I would certainly turn on HT for
> both CPUs. Obviously this is an extremely high level view and
> generalisation as
> yes workload can impact the potential performance gains for a HT
> system, but under "normal" applications and work patterns most
> "average" users might as well get the benefit from the CPUs they have
> purchased and use HT if available.
>
> --
>
> Regards,
>
> Mike
>
> "Charlie Russel - MVP" <> wrote in
> message news:...
>> If you turn it on in BIOS, you'll see an apparent 4 processors. But
>> before you do that, think about the workload your machine does.
>> Would it really benefit from 4 processors over 2? Certainly few if
>> any workstations need or would use 4 processors. Two? yes,
>> definitely, and I turn on HT on my single proc workstations. But
>> there is overhead in the # of processors, and hyperthreading is NOT
>> the same as actually having a dual core processor. So I would almost
>> certainly not turn on HT for an actual dual processor machine. On a
>> server, now, that's a different question and depends on the workload.
>>
>> --
>> Please, all replies to the newsgroup.
>> ======================
>> Charlie.
>> http://www.msmvps.com/xperts64/
>>
>>
>> Chuck Goldstein wrote:
>>> Hyperthreading is turned OFF in the bios. When should it be ON? My x64
>>> PC has 2 processors.
>>>
>>> Chuck

no, not at all negligible. That's an interesting result -- what application
is doing the rendering? Is it 32-bit? or 64-bit?

For me this sort of real user, real world, result is far more meaningful than
a zillion benchmarks.


--
Please, all replies to the newsgroup.
======================
Charlie.
http://www.msmvps.com/xperts64/


NNBXX wrote:
> I agree with you, Mike. I am using a dual Xeon EM64T workstation. Two
> processors without HT are far better than one for 3D rendering
> (almost twice as fast, actually). But with HT turned on for both
> processors, 3D rendering is still 15-20% faster, which is not
> negligible, IMO.
> "Mike Brannigan [MSFT]" <> wrote in
> message news:eZIU7$...
>> "Charlie Russel - MVP" <> wrote in
>> message news:...
>>> If you turn it on in BIOS, you'll see an apparent 4 processors. But
>>> before you do that, think about the workload your machine does.
>>> Would it really benefit from 4 processors over 2? Certainly few if
>>> any workstations need or would use 4 processors. Two? yes,
>>> definitely, and I turn on HT on my single proc workstations. But
>>> there is overhead in the # of processors, and hyperthreading is NOT
>>> the same as actually having a dual core processor. So I would
>>> almost certainly not turn on HT for an actual dual processor
>>> machine. On a server, now, that's a different question and depends
>>> on the workload.
>>
>>
>> Charlie,
>>
>> The "overhead" in managing multiple CPUs is far outweighed by the
>> additional processing capability provided (obviously only up to a
>> certain number of CPUs), so in the case of workstation class
>> machines (single or dual socketed) I would certainly turn on HT for
>> both CPUs. Obviously this is an extremely high level view and
>> generalisation as
>> yes workload can impact the potential performance gains for a HT
>> system, but under "normal" applications and work patterns most
>> "average" users might as well get the benefit from the CPUs they
>> have purchased and use HT if available.
>>
>> --
>>
>> Regards,
>>
>> Mike
>> --
>> Mike Brannigan [Microsoft]
>>
>> This posting is provided "AS IS" with no warranties, and confers no
>> rights
>>
>> Please note I cannot respond to e-mailed questions, please use these
>> newsgroups
>>
>> "Charlie Russel - MVP" <> wrote in
>> message news:...
>>> If you turn it on in BIOS, you'll see an apparent 4 processors. But
>>> before you do that, think about the workload your machine does.
>>> Would it really benefit from 4 processors over 2? Certainly few if
>>> any workstations need or would use 4 processors. Two? yes,
>>> definitely, and I turn on HT on my single proc workstations. But
>>> there is overhead in the # of processors, and hyperthreading is NOT
>>> the same as actually having a dual core processor. So I would
>>> almost certainly not turn on HT for an actual dual processor
>>> machine. On a server, now, that's a different question and depends
>>> on the workload. --
>>> Please, all replies to the newsgroup.
>>> ======================
>>> Charlie.
>>> http://www.msmvps.com/xperts64/
>>>
>>>
>>> Chuck Goldstein wrote:
>>>> Hyperthreading is turned OFF in the bios. When should it be ON? My x64
>>>> PC has 2 processors.
>>>>
>>>> Chuck

Does that mean you are not investing in Acer Ferrari again?
--
Andre
Extended64 | http://www.extended64.com
Blog | http://www.extended64.com/blogs/andre
http://spaces.msn.com/members/adacosta
FAQ for MS AntiSpy http://www.geocities.com/marfer_mvp/FAQ_MSantispy.htm

"Charlie Russel - MVP" <> wrote in message
news:...
> Interesting, Mike. I don't have a dual proc machine that also supports
> hyperthreading, so I certainly can't directly test this. But I am
> surprised that you think that a "normal" user (which on this group would
> definitely mean a power user) would see much benefit beyond two full
> procs. Guess I'm just going to have to afford some better machines.
>
> --
> Please, all replies to the newsgroup.
> ======================
> Charlie.
> http://www.msmvps.com/xperts64/
>
>
> Mike Brannigan [MSFT] wrote:
>> "Charlie Russel - MVP" <> wrote in
>> message news:...
>>> If you turn it on in BIOS, you'll see an apparent 4 processors. But
>>> before you do that, think about the workload your machine does.
>>> Would it really benefit from 4 processors over 2? Certainly few if
>>> any workstations need or would use 4 processors. Two? yes,
>>> definitely, and I turn on HT on my single proc workstations. But
>>> there is overhead in the # of processors, and hyperthreading is NOT
>>> the same as actually having a dual core processor. So I would almost
>>> certainly not turn on HT for an actual dual processor machine. On a
>>> server, now, that's a different question and depends on the workload.
>>
>>
>> Charlie,
>>
>> The "overhead" in managing multiple CPUs is far outweighed by the
>> additional processing capability provided (obviously only up to a
>> certain number of CPUs), so in the case of workstation class
>> machines (single or dual socketed) I would certainly turn on HT for
>> both CPUs. Obviously this is an extremely high level view and
>> generalisation as
>> yes workload can impact the potential performance gains for a HT
>> system, but under "normal" applications and work patterns most
>> "average" users might as well get the benefit from the CPUs they have
>> purchased and use HT if available.
>>
>> --
>>
>> Regards,
>>
>> Mike
>>
>> "Charlie Russel - MVP" <> wrote in
>> message news:...
>>> If you turn it on in BIOS, you'll see an apparent 4 processors. But
>>> before you do that, think about the workload your machine does.
>>> Would it really benefit from 4 processors over 2? Certainly few if
>>> any workstations need or would use 4 processors. Two? yes,
>>> definitely, and I turn on HT on my single proc workstations. But
>>> there is overhead in the # of processors, and hyperthreading is NOT
>>> the same as actually having a dual core processor. So I would almost
>>> certainly not turn on HT for an actual dual processor machine. On a
>>> server, now, that's a different question and depends on the workload.
>>>
>>> --
>>> Please, all replies to the newsgroup.
>>> ======================
>>> Charlie.
>>> http://www.msmvps.com/xperts64/
>>>
>>>
>>> Chuck Goldstein wrote:
>>>> Hyperthreading is turned OFF in the bios. When should it be ON? My
>>>> x64 PC has 2 processors.
>>>>
>>>> Chuck
>
>

No, the Ferrari is coming. Not sure when, but I'm still hopeful this month.
But might have to wait till august.

--
Please, all replies to the newsgroup.
======================
Charlie.
http://www.msmvps.com/xperts64/


Andre Da Costa [Extended64] wrote:
> Does that mean you are not investing in Acer Ferrari again?
>
> "Charlie Russel - MVP" <> wrote in
> message news:...
>> Interesting, Mike. I don't have a dual proc machine that also
>> supports hyperthreading, so I certainly can't directly test this.
>> But I am surprised that you think that a "normal" user (which on
>> this group would definitely mean a power user) would see much
>> benefit beyond two full procs. Guess I'm just going to have to
>> afford some better machines. --
>> Please, all replies to the newsgroup.
>> ======================
>> Charlie.
>> http://www.msmvps.com/xperts64/
>>
>>
>> Mike Brannigan [MSFT] wrote:
>>> "Charlie Russel - MVP" <> wrote in
>>> message news:...
>>>> If you turn it on in BIOS, you'll see an apparent 4 processors. But
>>>> before you do that, think about the workload your machine does.
>>>> Would it really benefit from 4 processors over 2? Certainly few if
>>>> any workstations need or would use 4 processors. Two? yes,
>>>> definitely, and I turn on HT on my single proc workstations. But
>>>> there is overhead in the # of processors, and hyperthreading is NOT
>>>> the same as actually having a dual core processor. So I would
>>>> almost certainly not turn on HT for an actual dual processor
>>>> machine. On a server, now, that's a different question and depends
>>>> on the workload.
>>>
>>>
>>> Charlie,
>>>
>>> The "overhead" in managing multiple CPUs is far outweighed by the
>>> additional processing capability provided (obviously only up to a
>>> certain number of CPUs), so in the case of workstation class
>>> machines (single or dual socketed) I would certainly turn on HT for
>>> both CPUs. Obviously this is an extremely high level view and
>>> generalisation as
>>> yes workload can impact the potential performance gains for a HT
>>> system, but under "normal" applications and work patterns most
>>> "average" users might as well get the benefit from the CPUs they
>>> have purchased and use HT if available.
>>>
>>> --
>>>
>>> Regards,
>>>
>>> Mike
>>>
>>> "Charlie Russel - MVP" <> wrote in
>>> message news:...
>>>> If you turn it on in BIOS, you'll see an apparent 4 processors. But
>>>> before you do that, think about the workload your machine does.
>>>> Would it really benefit from 4 processors over 2? Certainly few if
>>>> any workstations need or would use 4 processors. Two? yes,
>>>> definitely, and I turn on HT on my single proc workstations. But
>>>> there is overhead in the # of processors, and hyperthreading is NOT
>>>> the same as actually having a dual core processor. So I would
>>>> almost certainly not turn on HT for an actual dual processor
>>>> machine. On a server, now, that's a different question and depends
>>>> on the workload. --
>>>> Please, all replies to the newsgroup.
>>>> ======================
>>>> Charlie.
>>>> http://www.msmvps.com/xperts64/
>>>>
>>>>
>>>> Chuck Goldstein wrote:
>>>>> Hyperthreading is turned OFF in the bios. When should it be ON? My x64
>>>>> PC has 2 processors.
>>>>>
>>>>> Chuck