Re: Z420 CPU fan not increasing under load

Hi SDH, thanks for replying and confirming that the larger heatsink and airflow baffle will fit together, hopefully this will help keep the system a bit cooler overall. I'm hoping to squeeze a few more years out of this machine before having to drop the cash on a new one (which at this point looks like it might be a used Z440 but time will tell) -- these Zx20 series machines are still solid performers especially for their age, and at this point the power supply is really what's holding me back in upgradability on the graphics side.

I've been playing around with ThrottleStop as well in conjunction with XTU, and so far have managed to dial in a configuration that I'm happy with to achieve a "power efficient" overclock which also keeps the temperatures low when idle.

From my experience so far, XTU 6.5.1.321 seems to be the most solid version to use with Windows 10 and BIOS rev. 03.94 with Fast Startup disabled as you've mentioned, otherwise XTU will reset the multiplier values at random on startup. I've also enabled the Ultimate Performance power plan which keeps Windows from parking CPU cores to achieve lower latency and then have ThrottleStop doing the rest of the work.

For what it's worth, here's a quick run-down of how I did this on my system:

1. Set the power profile to either High Performance or Ultimate Performance so that Windows does not control the processor's clock speed / SpeedStep functionality.
2. Install XTU, reboot, and apply the maximum stable multiplier for all cores. Reboot again and ensure that the multiplier settings stuck correctly (CPU-Z or HWMonitor works fine here).
3. Install ThrottleStop and configure your profiles. For my every-day usage profile I have used these settings, adjust accordingly:
   1. Check Set Multiplier and set it to the maximum turbo ratio value.
   2. Check Power Saver to enable the CPU to throttle back down to minimum clock speed based on load.
   3. Click TRL and set the multiplier per active cores as desired. On this profile I was a bit more conservative, with a multiplier value of 43 for up to 3 cores and 42, 41, 40 for cores 4-6 respectively).
   4. Click Options and set PowerSaver C0% to 40 (default is 35). Note: This is completely subjective based on your workloads and how fast you want the processor to ramp it's clock speed up/down.
   5. Also check Start Minimized and Minimize on Close so that ThrottleStop's UI is silent on boot and that it remains running in the background, then hit OK to close the Options dialog.
   6. Don't forget to click Save in the main ThrottleStop window so that the settings are applied when it runs.
4. Open the Windows Task Scheduler and create a new entry for ThrottleStop to run on startup:
   1. Name: ThrottleStop
   2. Actions: Start a program > Path to ThrottleStop.exe.
   3. Trigger: At log on > At log on of any user.
   4. Ensure that Run with highest privileges option is checked.
5. Reboot again and ensure that your settings are correctly applied on boot.