Hyperthreading and Windows XP

[BootMe]

Ok, i'm a little confused here. How would i enable Hyperthreading in Windows XP??

I see reports that installing service pack 1 enables the feature. I have also heard the pressing f5 during windows xp intial install and selecting the multiprocessor acpi HAL. Which is the proper way to enable hyperthreading??

 

[Chris A]

That is a good question that I unfortunaly do not have the answer to. I have been watching this thread hoping to find out. I had heard that XP pro was the one with Hyperthreading not XP home..

 

[Tetsuo]

Your mobo has to support it, just go into your bios, and there should be an option "enable hyperthreading" or something along those line

 

[Chris A]

Ok here it is.

Win XP Home Edition: A Bad Choice Gets Worse





Hyperthreading? Look Elsewhere

Intel is preparing to start providing hyperthreading in its mainstream processors, not just its server-oriented products. At a very simplistic level, hyperthreading treats one processor as two, harnessing unused clock cycles to process two separate streams of instructions. The performance gain can be anywhere from 15 to 30 percent, depending on the workload and instruction mix. It requires an operating system and application software that support multiple processors.


As you've no doubt guessed by now, Win XP Home doesn't support multiple processors. Win XP Pro does, and so does Windows 2000. Microsoft has no plans to add multiprocessor support to Home, having figured that home users would never need this feature, even though Intel had warned that it was coming?or else those who wanted the added capability could pay for a copy of Pro. Intel, meanwhile, is trying to cement and extend its performance lead by combining ever-faster CPUs with hyperthreading to handle multimedia processing and other high-end consumer tasks.

Do you pay more for your gasoline when you drive a minivan instead of a sedan? Why should you pay more for your operating system just because you choose a hardware platform with higher capacity? We can only hope the Microsoft folks will see the absurdity in the arbitrary differences between Win XP Home and Pro and make Pro the sole standard, at a price that keeps systems affordable. Or maybe they just like to cause as many problems as they solve.

Found here..

 

[oldfart]

What Intel says:

Microsoft* Windows* Operating System Desktop Based PCs
The following desktop operating systems include optimizations for HT Technology and are currently eligible to carry the new Intel® Pentium® 4 Processor with HT Technology logo:
Microsoft* Windows* XP Professional Edition
Microsoft* Windows* XP Home Edition

The following desktop operating systems are not recommended for use with Hyper-Threading Technology. If you are using one of the following desktop operating systems, it is advised that you should disable Hyper-Threading Technology in the system BIOS Setup program:

Microsoft Windows 2000 (all versions)
Microsoft Windows NT* 4.0
Microsoft Windows Me
Microsoft Windows 98
Microsoft Windows 98 SE

Linux* Operating System Desktop Based PCs
The following Linux operating systems include optimizations for HT Technology and are currently eligible to carry the Intel® Pentium® 4 Processor with HT Technology logo:
Red Hat Linux* 9 (Professional and Personal versions)
SuSE Linux* 8.2 (Professional and Personal versions)
Red Flag Linux* Desktop 4.0

 

[Chris A]

Thanks oldfart you cleared up a few things for me.

 

[Canterwood]

OK, let me clear something up here.

Its all about physical and logical processors in hyperthreading.

XP Home supports 1 physical cpu ie 1x p4 3ghz.
XP Pro support 2 physical cpu's ie 2x p4 3ghz
However when hyperthreading is enabled, the the operating system sees two cpu's. 1 physical and 1 logical.
Although XP Home only supports one physical cpu, it can make use of hyperthreading as it can differentiate between physical and logical cpu's so will see two cpu's.
XP Pro can use two physical cpu's with hyperthreading (ie it sees a total of 4 cpu's. 2 physical 2 logical.)
Windows 2000 CAN make use of hyperthreading, but cant tell the difference between physical and logical cpu's. (Sees a hyperthreading cpu as two physical cpu's.

As Tetsuo says, you need a motherboard that supports hyperthreading and you enable it in the bios.
A fresh install of Window XP Home/Pro or 2000 will install as a multiprocessor PC with hyperthreading enabled.
However if you've already got Windows XP/2k installed, then there's no need to reinstall as you just need to upgrade the Computer to a "mutiprocessor PC" through Device Manager.

Hope this helps.

 

[vaporize]

How do I quickly find out if my system has HyperThreading enabled?

 

[EdipisReks]

sisoft sandra.

 

[Quackmaster]

Originally posted by: vaporize
How do I quickly find out if my system has HyperThreading enabled?

or just open task manager. You should see two logical cpus with their history graphs

 

[BOBDN]

Originally posted by: vaporize
How do I quickly find out if my system has HyperThreading enabled?

You can download freeware - CPU-Z. On the CPU tab under Processor Selection click the drop down arrow. If hyper-threading is enabled you'll have CPU 1 (Physical) and CPU 2 (Logical).

 

[bgeh]

Originally posted by: vaporize
How do I quickly find out if my system has HyperThreading enabled?

press CTRL+ALT+DELETE to open Task Manager and under the Performance tab, you should see 2 CPU's

 

[vaporize]

cool, i dont have hyperthreading yet. I am going to get soon. Are the 2 graphs in the performace tab in task manager identical? Do they show the same peaks when you are running something?

 

[Quackmaster]

no, they show only that logical cpus history. Play a DVD and run another less intensive program and you'll see. It's pretty

 

[BootMe]

Here's what i did. I didnt have winxp install beofer it idid this and i also have windows xp pro.

Enabled hyperthreading in bios. Installed windows xp. Checked the performance tab of task manager. Saw two processors. Assumed i had hyperthreading enabled.

 

[bacillus]

hmm, as I dual boot win98 & xp, me wonders what problems will be seen if HT is enabled in bios when using win98se?
anyone know for sure?

 

[lookin4dlz]

Originally posted by: Canterwood
OK, let me clear something up here.

Its all about physical and logical processors in hyperthreading.

XP Home supports 1 physical cpu ie 1x p4 3ghz.
XP Pro support 2 physical cpu's ie 2x p4 3ghz
However when hyperthreading is enabled, the the operating system sees two cpu's. 1 physical and 1 logical.
Although XP Home only supports one physical cpu, it can make use of hyperthreading as it can differentiate between physical and logical cpu's so will see two cpu's.
XP Pro can use two physical cpu's with hyperthreading (ie it sees a total of 4 cpu's. 2 physical 2 logical.)
Windows 2000 CAN make use of hyperthreading, but cant tell the difference between physical and logical cpu's. (Sees a hyperthreading cpu as two physical cpu's.

As Tetsuo says, you need a motherboard that supports hyperthreading and you enable it in the bios.
A fresh install of Window XP Home/Pro or 2000 will install as a multiprocessor PC with hyperthreading enabled.
However if you've already got Windows XP/2k installed, then there's no need to reinstall as you just need to upgrade the Computer to a "mutiprocessor PC" through Device Manager.

Hope this helps.

Thanks. When this first came up I read on Microsoft's site that Win Xp Home supported Hyperthreading.

 

[Ogo]

When I enabled HT in the bios and used it in Win2000, I noticed a 15-20% DROP in game performance. (Q3, ut2k3, CS).

 

[Quackmaster]

Originally posted by: Ogo
When I enabled HT in the bios and used it in Win2000, I noticed a 15-20% DROP in game performance. (Q3, ut2k3, CS).

Some apps do not use hyperthreading efficiently due to lack of programing. So you have to evalute what Hyperthreading does for YOUR system. Me? I can run c&c Generals at 1600x1200 everything maxed while running Prime 95 and task manager (for cpu history) in the background and it works flawlessly. So obviously I like it, but it ain't even close to being a hardware SMP [simultaneous Multi- Processing (or Processors)] system.

Quake 3 on the other hand sucks even with two actual CPUs running SMP. Carmack enabled a switch to enable SMP in the console for Q3. I tried it, it blows chunks compared to a single processor system. I also saw a lot of the same being experienced by others. I did not see even ONE person who got a performance boost out of SMP in Q3. Likewise Counterstrike is Quake 2 code-based so it's the same bowl of soup.

I dunno about Unreal tho.

 

[Thor86]

Originally posted by: Ogo
When I enabled HT in the bios and used it in Win2000, I noticed a 15-20% DROP in game performance. (Q3, ut2k3, CS).

You can enable it in the BIOS, but your OS doesn't support it.

 

[EdipisReks]

Originally posted by: Quackmaster

Originally posted by: Ogo
When I enabled HT in the bios and used it in Win2000, I noticed a 15-20% DROP in game performance. (Q3, ut2k3, CS).

Some apps do not use hyperthreading efficiently due to lack of programing. So you have to evalute what Hyperthreading does for YOUR system. Me? I can run c&c Generals at 1600x1200 everything maxed while running Prime 95 and task manager (for cpu history) in the background and it works flawlessly. So obviously I like it, but it ain't even close to being a hardware SMP [simultaneous Multi- Processing (or Processors)] system.

Quake 3 on the other hand sucks even with two actual CPUs running SMP. Carmack enabled a switch to enable SMP in the console for Q3. I tried it, it blows chunks compared to a single processor system. I also saw a lot of the same being experienced by others. I did not see even ONE person who got a performance boost out of SMP in Q3. Likewise Counterstrike is Quake 2 code-based so it's the same bowl of soup.

I dunno about Unreal tho.

i've always seen quake3 get a decent boost with SMP. dual 366 celerons @ 550 used to be the Quake III platform.

 

[oldfart]

I just tried it with HT....oh yeah, big performance hit! Back to seta r_smp "0" we go (not that I actually play Q3 anyway).

 

[TerryMathews]

Originally posted by: Quackmaster
Quake 3 on the other hand sucks even with two actual CPUs running SMP. Carmack enabled a switch to enable SMP in the console for Q3. I tried it, it blows chunks compared to a single processor system. I also saw a lot of the same being experienced by others. I did not see even ONE person who got a performance boost out of SMP in Q3. Likewise Counterstrike is Quake 2 code-based so it's the same bowl of soup.

Hate to pick nits, but here I go. The SMP switch in Q3 offloads geometry and world data to the second processor. With the advent of HW T&L graphics cards, only the world data gets offloaded to the second processor. The problem here lies with timedemos. In timedemos, the world data is static, leaving the second processor nothing to do and making the game look slower.

In a real game, with bots or humans, running r_smp 1 would yield a higher overall performance, but possibly lower peaks. Like if you graphed your Q3 performance, the single proc might have higher peaks, but the dually would have more area under the graph, meaning higher overall frame rates.

Also, Counterstrike is a Half-Life based game, not Q3.

EDIT: And another point I wanted to make: HyperThreading is not SMP. It allows two seperate programs to take advantage of different parts of the CPU. For example, one process can use the FPU and the other the ALU. Games typically only make use of one piece of the core.

 

[cirocorby]

u need to get your fax straight before you go and give advise hyper threading works on home & pro XP

 

[TerryMathews]

Originally posted by: cirocorby
u need to get your fax straight before you go and give advise hyper threading works on home & pro XP

It does. HyperThreading at the Inquirer. HyperThreading support is one of the major selling points of WinXP vs. Win2k.