# Why do the maximum frequencies of TX2 CPUs drop to 1.4GHz when more than 4 cores are up? **URL:** \ **Category:** Jetson TX2\ **Created:** [July 10, 2019, 6:53pm UTC](https://forums.developer.nvidia.com/t/why-do-the-maximum-frequencies-of-tx2-cpus-drop-to-1-4ghz-when-more-than-4-cores-are-up/77819 "2019-07-10T18:53:37Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![hecnl4o](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@hecnl4o](https://forums.developer.nvidia.com/u/hecnl4o)\ **Post date:** [July 10, 2019, 6:53pm UTC](https://forums.developer.nvidia.com/t/why-do-the-maximum-frequencies-of-tx2-cpus-drop-to-1-4ghz-when-more-than-4-cores-are-up/77819/1 "2019-07-10T18:53:37Z")
Hello, The TX2 SOM datasheet says: “CPU Maximum Operating Frequency: 1-4 core = up to 2.0GHz; greater than 4-core = up to 1.4GHz” Can you please tell us the reason why the max freq drops to 1.4GHz when more than 6 cores are up? When I put all 6 cores online, the following Linux command shows all 6 cores are still at 2GHz. Is the reading from Linux reliable? cat /sys/devices/system/cpu/cpu\*/cpufreq/cpuinfo\_cur\_freq 2021000 2034000 2036000 2017000 2024000 2026000 Thanks for your help! ---
**Author:** ![hecnl4o](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@hecnl4o](https://forums.developer.nvidia.com/u/hecnl4o)\ **Post date:** [July 11, 2019, 7:21pm UTC](https://forums.developer.nvidia.com/t/why-do-the-maximum-frequencies-of-tx2-cpus-drop-to-1-4ghz-when-more-than-4-cores-are-up/77819/2 "2019-07-11T19:21:23Z")
Is the frequency drop due to the limited power supply to CPU subsystem? ---
**Author:** ![linuxdev](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/linuxdev/32/10243_2.png) [@linuxdev](https://forums.developer.nvidia.com/u/linuxdev)\ **Post date:** [July 11, 2019, 8:24pm UTC](https://forums.developer.nvidia.com/t/why-do-the-maximum-frequencies-of-tx2-cpus-drop-to-1-4ghz-when-more-than-4-cores-are-up/77819/3 "2019-07-11T20:24:15Z")
Have you set a particular power model? “sudo nvpmodel -m 0” makes the maximum performance range available. If you want to force to max performance within a given model, then run “sudo jetson\_clocks” after switching to the desired model (for older releases it is “sudo ~ubuntu/jetson\_clocks.sh”). ---
**Author:** ![Trumany](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/trumany/32/14043_2.png) [@Trumany](https://forums.developer.nvidia.com/u/Trumany)\ **Post date:** [July 12, 2019, 2:27am UTC](https://forums.developer.nvidia.com/t/why-do-the-maximum-frequencies-of-tx2-cpus-drop-to-1-4ghz-when-more-than-4-cores-are-up/77819/4 "2019-07-12T02:27:39Z")
The power consumption would drive the temperature of the die beyond its maximum operating point, so it is necessary to throttle the freq lower. ---
**Author:** ![hecnl4o](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@hecnl4o](https://forums.developer.nvidia.com/u/hecnl4o)\ **Post date:** [July 12, 2019, 2:33am UTC](https://forums.developer.nvidia.com/t/why-do-the-maximum-frequencies-of-tx2-cpus-drop-to-1-4ghz-when-more-than-4-cores-are-up/77819/5 "2019-07-12T02:33:05Z")
Thank you, Trumany! ---
**Author:** ![hecnl4o](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@hecnl4o](https://forums.developer.nvidia.com/u/hecnl4o)\ **Post date:** [July 15, 2019, 10:03pm UTC](https://forums.developer.nvidia.com/t/why-do-the-maximum-frequencies-of-tx2-cpus-drop-to-1-4ghz-when-more-than-4-cores-are-up/77819/6 "2019-07-15T22:03:19Z")
Hi, Trumany, I have some follow-up questions for this topic. If we have a very strong CPU fan on top of SOM and keep the CPU cores cool, can the CPU cores still keep 2GHz frequency? Will the HW or nVIDIA bootloader limit the max freq to 1.4GHz even if the temperature of CPU core is low? Thanks Yan ---
**Author:** ![Trumany](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/trumany/32/14043_2.png) [@Trumany](https://forums.developer.nvidia.com/u/Trumany)\ **Post date:** [July 16, 2019, 3:15am UTC](https://forums.developer.nvidia.com/t/why-do-the-maximum-frequencies-of-tx2-cpus-drop-to-1-4ghz-when-more-than-4-cores-are-up/77819/7 "2019-07-16T03:15:40Z")
Yes, it is limited for most use case. ---
**Author:** ![hecnl4o](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@hecnl4o](https://forums.developer.nvidia.com/u/hecnl4o)\ **Post date:** [July 16, 2019, 4:10am UTC](https://forums.developer.nvidia.com/t/why-do-the-maximum-frequencies-of-tx2-cpus-drop-to-1-4ghz-when-more-than-4-cores-are-up/77819/8 "2019-07-16T04:10:29Z")
Hi, Trumany, Thank you for confirming the throttling of the max freq is enforced by the design regardless of the CPU temperature! What still confuses me is the output of CPU frequencies by Linux. When I put all 6 cores online and run CPU intensive stress testing (CPU scaling\_governor is set to performance mode), the following Linux command shows all 6 cores are still at 2GHz either during the testing or after the testing. Is the reading from this Linux command reliable? Is there any other Linux command (such as reading other sysfs node) which can show accurate CPU frequencies of cores on TX2? cat /sys/devices/system/cpu/cpu\*/cpufreq/cpuinfo\_cur\_freq 2021000 2034000 2036000 2017000 2024000 2026000 Thank you! ---
**Author:** ![nadeemm](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/nadeemm/32/367020_2.png) [@nadeemm](https://forums.developer.nvidia.com/u/nadeemm)\ **Post date:** [October 18, 2021, 6:33pm UTC](https://forums.developer.nvidia.com/t/why-do-the-maximum-frequencies-of-tx2-cpus-drop-to-1-4ghz-when-more-than-4-cores-are-up/77819/9 "2021-10-18T18:33:08Z")
Closed on October 18, 2021, 6:33pm UTC