Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Is is ever possible that a given computer has several processors among which only some have Hyper Threading technology and others do not?

My problem is that I use hardcore code like here for identifying which logical processors map to which physical cores. This code misbehaves when run in a virtual machine. My current intent is to first check whether the processor has Hyper Threading at all but I need to be sure that all other processors in the system also have (or not have) Hyper Threading.

Is it possible that only some processors in a system have Hyper Threading and others do not?

share|improve this question
This should probably be asked at – nik Sep 17 '09 at 9:19
Nope, that's not programming related, it's a pure hardware problem. – sharptooth Sep 17 '09 at 9:34
up vote 2 down vote accepted

I think the most common kind of multi CPU support is Symmetric Multiprocessing (SMP) which requires identical processors. I believe this is true for Windows and most Linux distributions.

share|improve this answer
right - mixing CPUs is highly frowned-upon; they need to bethe same everything - cache, speed, number of cores, etc – warren Sep 17 '09 at 10:58
@warren They sometimes need to be the same revision number of a particular processor as a friend of mine found out to his cost. I remember seeing a chart he found showing which revisions of a Pentium II-300 would SMP happily together. – Dave Webb Sep 17 '09 at 11:03

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.