Windows Defender can Significantly Impact Intel CPU Performance, We have the Fix

[unclewebb]

my all core clocks of 4700mhz show around mid 46xx in Defender mode -0x222

The actual clocks are consistent. The problem is that Windows Defender and HWiNFO are constantly fighting over control of the monitoring timers. HWiNFO sets the timers to mode 3 so it can accurately determine the effective clocks. Windows Defender comes along and changes the timers back to mode 2. This happens over and over again. Kind of like two people trying to share a single stop watch. This is what prevents HWiNFO from accurately measuring the effective clock speed. The clock speed has not changed. Just the ability to correctly monitor the effective clock speed has changed.

Monitoring software should be able to request exclusive access to these system timers. That would help prevent any fights like this over their use. The shared timer model that Intel uses is flawed.

 

[ThrashZone]

Hi,
Yeah I disable the effective clock monitoring
Also in hwinfo settings/ safety uncheck periodic poling as well.

 

[Ed_1]

The actual clocks are consistent. The problem is that Windows Defender and HWiNFO are constantly fighting over control of the monitoring timers. HWiNFO sets the timers to mode 3 so it can accurately determine the effective clocks. Windows Defender comes along and changes the timers back to mode 2. This happens over and over again. Kind of like two people trying to share a single stop watch. This is what prevents HWiNFO from accurately measuring the effective clock speed. The clock speed has not changed. Just the ability to correctly monitor the effective clock speed has changed.

Monitoring software should be able to request exclusive access to these system timers. That would help prevent any fights like this over their use. The shared timer model that Intel uses is flawed.

Yeah, I saw the fighting happening while running HWinfo64, so the effective clock is just a reporting issue caused by defender counters.

 

[sodium]

Just updating as of the date of this post the defender bug is still a problem so I guess it's never going to get fixed. optimized defaults in bios, 12700k and 4800 JEDEC DDR5. Fully updated windows 11 home 23H2, OS build 22631.3296. Latest bios/ME firmware on MSI Z690. The motherboard doesn't matter with this bug since the same CPU in an ASROCK motherboard had the same problem.

Cinebench R23.200
21382 - the bug is active, effective clock speeds in hwinfo are all throttling slightly lower than normal.
22620 - bug is fixed by simply opening and then closing Throttlestop. Effective clock speeds are now reaching advertised default boost.

 

[unclewebb]

bug is fixed by simply opening and then closing ThrottleStop.

If Windows Defender Boost is checked in the ThrottleStop 9.6 Options window, you should continue to get maximum performance whether ThrottleStop is running or not. If you do a sleep resume cycle, you will need to start ThrottleStop again.

I prefer to just leave ThrottleStop running in the background with it minimized to the system tray. Being able to see the CPU temperature in the system tray helps me keep an eye on things. That makes it easier to see when some background process has gone rogue. ThrottleStop is very efficient. If you want to absolutely minimize CPU usage, press the Stop Data button. CPU usage will be close to zero with reduced data monitoring.