03-24-2016 07:10 AM
I recently purchased a T460S and would like to disable CPU hyperthreading. I couldn't find any settings in the BIOS related to hyperthreading. Is there anyway to disable it?
03-24-2016 10:48 AM
Hello and welcome,
I don't think it's a BIOS option on these machines. There is a way to control this at the OS level, but I can't tell if it sets numer of cores, or number of hyperthreads. FWIW:
The document refers to Windows 7 but it's there in Win 10 on my T450s too.
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03-24-2016 10:53 AM
03-28-2016 07:39 AM
03-28-2016 07:50 AM
The feature was removed due to lack of use-cases, and a desire to remove obselete settings/options which do not benefit anyone. This is why I asked to understand what you are trying to do.
If single-core performance is what you want, I believe there are other ways to accomplish this.
03-28-2016 08:09 AM
Sorry, but that's totally wrong reason to remove this setting. A lot of people that I know off in scientific community will disable hyper-threading right away.
I'd love to hear what your suggestions are on achieving optimal single core perfomance without disabling hyper-threading! Because that sounds like magic dust to me!
04-02-2016 09:15 PM
it is not a questionf of single core vs. multiple cores. But rather multiple physical cores vs. multiple logical cores. This is an important distinction. There are many instances where, as a user, I prefer multiple physical cores instead of multiple logical cores. I'll refer you to one of the discussions on matlab website http://www.mathworks.com/matlabcentral/answers/80129-definitive-answer-for-hyperthreading-and-the-pa...
04-04-2016 07:18 PM
Earlier you said, "I do a lot of scientific computing and most of the programs that I use benefit greatly from single core performance." It was confusing. I am rather surprised that the overhead of hyperthreading is causing a significant performance drop... but to each his own.