Did you disable "Intel SpeedStep Technology" in the BIOS?
That is Intel's hardware power management. I always disable that. Many OEM computers do not allow access to that setting.
Yep, been doing this for quite some time unless I'm intentionally trying to down clock my CPU in which I will then enable CEIST (CPU Enhanced Intel SpeedStep Technology), enable the Balanced power plan so the OS will hook into it then reset the min power % setting in the Advanced Settings section to a % level that will correspond to the lower CPU clock frequency that I'm wanting to use for testing......if I want to lock it there then set the power max % setting to 5% above the new min power % setting to keep it there......... Just another method of using the Intel CPU power management\Windows Balanced power plan to achieve a similar result vs using the High Performance plan.............
Works as advertised, too. This is the method that I used to set the CPU clock speeds to the 2.7GHz that was being recorded during the 2nd video that I posted in another thread to demonstrate that by using 1 of these type of CPU's the CPU clock speed wasn't a major factor in the CPU's capability to stream massive amounts of data out quickly when there are enough CPU physical cores available to process the threads across a large L3 cache & SMP branch pipe structure running at 3.0GHz speed................
But I believe that Intel has also inserted the old baseline SpeedStep algorithim strictly at the CPU hardware level & didn't allow any outside access to it. I vaguely remember reading some article some years back that brought this to light.....I think this was done after the Prescott fiasco to "protect" subsequent Intel CPU's from being overheated but can't say for sure. Still researching for verification of this.............have slept too many days afterwards..............
This is the only "theory" that makes sense of what I was seeing w\ my I7 5820K CPU, otherwise TurboBoost should have it hit 3.7GHz & stay there as long as the CPU thermal TDP threshold wasn't encroached regardless of CPU load....CPU was running at 55*C-57*C during this testing which is nowhere near the TDP threshold for this Haswell-E chip.
My testing shows to confirm that this is the case as I had CEIST & Platform Power Management disabled during subsequent test runs using the overlay setup I mentioned earlier to show this data in real time....I could clearly see the CPU core clock speeds occasionally drop down to 1.5GHz then go back up to 3.7GHz....all while under a running game load using the Dx11 version of AHIII.
If I find this info I will post it.
BTW.......if Intel CEIST is enabled it will also override & defeat Intel's TurboBoost when it detects light CPU core loads causing stuttering & other issues that we sometimes erroroneously relate to a GPU issue..............been there, done that.
FYI..........................
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