Windows 10: How to enable and disable instruction extensions like AVX, AVX2 and AVX512?

How to enable and disable instruction extensions like AVX, AVX2 and AVX512 in Windows 11? I have tried to find a PowerShell command to do this without success. Some of these in different processors may be enabled or disabled by default. I would like to be able to see the current state and be able to set it as desired. Thanks, John.

:)

 

i5 6500 3.6GHz on 4 cores?

Ask the people that are/were overclocking locked Skylake.
Non-K Skylake Overclocking Hurts AVX2 Performance, Problem Related to "256-bit Vector Warm-up"

 

Instructions to change board?

Boot off of the windows CD, repair your XP partition (hopefully you won't have to reinstall windows), install drivers, and you're good to go. You'll see dual channel mode in the BIOS splash screen results from POST. It'll be pretty obvious *Stick Out Tongue . Here's a list of general tweaks for the 939Dual-SATA2.
Step one- Set time, date
Step two- In CPU settings, disable cool n quiet, set memory clock to DDR400, play with memory timings (CAS-TRAS-TRP-TRCD), which are listed in the bios in the order CAS, TRCD, TRAS, and TRP. EDIT- new BIOS's mess around with this order, can't be too sure on it, but yeah at least you know what the RAM timings stand for *Big Grin .
Leave MA timing at 2T unless you think your system can handle 1T
Step three- in Chipset settings, enable onboard LAN, disable onboard Audio, disable AGP fast write, set primary graphics adapter, and set CPU-NB and NB-SB link speed to 1000mhz.
Step four- in IDE, disable controllers you aren't using. On all drives detected, enable SMART if you can and set PIO/DMA as high as they will go.
Step five- Enable legacy USB support
Step six- Set password if you're worried about anyone screwing around with your BIOS settings
Step seven- Configure your boot sequence. I reccomend hard drive first, optical drive second, and floppy drive third.
Step eight- Save changes, boot into XP, and enjoy your computer.

 

CPU downclocking during Prime95 run.

To know more about AVX read this and the links at the bottom of the article(you don't need to understand all of it, but the basics are squeezed in there). Introduction to Intel® Advanced Vector Extensions | Intel® Software

Also:

Advanced Vector Extensions - Wikipedia

And anything running FPU's(floating point calculations) these days.