By turning off hyper threading in bios does it effect performance in any way ?

[Darksider]

I had to turn mine off just to play an old game from 2010

[Omega]

It will massively decrease your multi threading performance. Keep it enabled.

[Overseer]

It can even give you better performance in some games. It's an odd one but on average you want it on, especially factoring in the OS.
To play older games you do not need mess with BIOS setting, you can just use core affinity in the OS. For Steam all you have to do is change the steam.exe affinity before you run the game through Steam. Affinity is passed on down the tree.

[A&A]

If CPU's threads are enough for your multitasking needs, l don't see a problem.

[Introverted Gamer]

Publicado originalmente por smallcat:

i am hearing for the first time that hyperthreading might prevent an application/game from properly running . What is that game ?

Some games I can name is The Saboteur that game will not run on 4 Cores and above. Another is The Sim 2 that game runs like garbage on anything more than 1 Core, and The Sims 3, Going beyond 3 Cores in that game gives worse performance.

[A&A]

There is a difference between cores and threads.

[Omega]

Publicado originalmente por A&A ✠:

There is a difference between cores and threads.

Yes, but your program does not know that. And the CPU schedular may or may not either.

[Introverted Gamer]

Publicado originalmente por A&A ✠:

There is a difference between cores and threads.

Many old games does not know how to use Multi Threads, purely rely on Single Core.

[Joke]

You can set "processor affinity" for a running program.
This means telling Windows which cores (real or hyperthread virtual) a program can use, so if the program can only run on up to 4 cores, you assign 4 cores to it.

Right-click the process in task manager, and choose "Properties", which takes you to the info tab and there a new right-click takes lets you open the affinity window. Set a mark in the checkboxes for the cores you want to use.

I had to to that for a game (I can't remember which now), and it worked well.
Only problem is that I had to do it each time I started the game. (yes, you can create a bat-file to do it, but I didn't bother)

[A&A]

The CPU schedular is a part of the OS, not the program.

A process is an execution of a program and it is a combination of required threads.

It's true that older CPU scheduling algorithms made mistakes thinking the extra threads for physical cores, causing performance penalty, but that's in the XP era.

[Rod]

Publicado originalmente por smallcat:

The OP PC is so powerful that it wont be an issue if HT is disabled .

He would prob get more fps in a 2010 game by disabling HT, And boosting by another 100mhz on all cores.

[A&A]

Publicado originalmente por Rod:

Publicado originalmente por smallcat:

The OP PC is so powerful that it wont be an issue if HT is disabled .

He would prob get more fps in a 2010 game by disabling HT, And boosting by another 100mhz on all cores.

No he has to underclock all cores except one which will be overclocked to 6.9GHz and manually scheduled to work only for those games :D

And disabling virtual machine support will help by 5% why not who uses virtual machines anyway, or let's remove the rest of the instruction sets, who's going to use them?

[Darksider]

Publicado originalmente por smallcat:

Further more , the OP could even benefit from disabling HT because this can make FPS more stable in gaming i.e. smoother gameplay experience .That laptop could afford this change .

Thanks well it's off and everything seems to be running fine games wise even AAA 2023 Titles

[Darksider]

Publicado originalmente por smallcat:

i am hearing for the first time that hyperthreading might prevent an application/game from properly running . What is that game ?

Witcher 2

[hawkeye]

All games use multiple threads. Whilst the game itself might have just one main thread that does most of the work (80% in the original Skyrim for example) Direct X and other drivers and dynamic link libraries need to use cpu threads as well.

Turning off hyperthreading can introduce stuttering, which can need frametime monitoring to detect.

[_I_]

if the game tries to use more threads than the cpu has cores, it can cause stuttering
but most of the time, having ht enabled will help with other background tasks while gaming

even the first p4 single core with smt/ht, it hurt performance by disabling it by quire a bit