Turning off Hyperthreading

saibhne

Hi All,
I've just bought a new Dell Dimension and I need to turn off the hyperthreading feature. Can anyone point me in the right direction about how to do that? OS is windows XP.

Cheers!

Simon.

seamus

I'd say your first stop is to go into your Device Manager, and then into the Properties of your processor.

Failing that, try the Advanced tab of the system properties and have a look under Performance.

Truth is, I'm only guessing.

BigEejit

I thought that the OS just detects a hyperthreading processor and turns it on .... the place to turn it off should be in the bios

seamus

BigEejit wrote:

I thought that the OS just detects a hyperthreading processor and turns it on .... the place to turn it off should be in the bios

I'm not sure. From what I've read just now, Hyperthreading is supported as a virtual second processor in XP.

There's a good chance that just removing a second physical processor without informing XP could cause some hassle, so the same chance exists if you just remove a virtual processor without telling XP.

On the other hand it might notice it on boot and carry on as normal.

Terra

you just go into the bios of the dell computer and turn it off.

qwertz

Why do you want to turn it off? I thought Hyperthreading is a good thing. Just curious.

fatherdougalmag

Some drivers aren't multiprocessor compliant so typically a quick fix is to disable HT in the BIOS. Be warned though, even though you turn of HT in the BIOS and Windows only reports one CPU the multiprocessor HAL (hal.dll) and kernel (ntoskrnl.exe) are still used. This just means that whilst disabling HT might fix some low, driver level issues it's not a panacea.

saibhne

Thanks all - I disabled it in the BIOS as suggested - simple as that.
I'm using the machine to record music and will be installing PRO-tools by digidesign, their advice is to turn it off. Apparently hyperthreading's main benefit is if you are running multiple tasks and those tasks are very resource intensive. Otherwise if the machine isn't challenged by these multiple tasks then it seems hyperthreading can have a slightly negative effect on performance.

qwertz

Thanks for clarifying it. So basically hyperthreading is an evil technology. Evil Evil Evil.

Dempsey

qwertz wrote:

Thanks for clarifying it. So basically hyperthreading is an evil technology. Evil Evil Evil.

I wouldnt say that at all.

qwertz

I was joking but you know that.