Author: parsec
Subject: AMD Ryzen 1800x CPU thermal throttling
Posted: 15 Oct 2017 at 9:47am
I have these temperature related throttling options in the UEFI/BIOS of my X370 Killer SLI/ac board. I'm not sure if your board's UEFI will have these screens and options:
Advanced\AMD CBS\Zen Common Options\Custom Pstates / Throttling:
Relaxed EDC Throttling (default value Auto, settings of Auto, Enabled, Disabled)
According to this option's description, when set to Disabled, full throttling protection is enabled.
Enabled means reduce the amount of time the processor will throttle.
Auto is AMD recommendation, which is the same as Disabled. So the default setting is full throttling enabled.
So it seems if you set this option to Enabled, the processor will throttle less, which I assume means it allows a higher CPU temperature.
H/W Monitor:
Over Temperature Protection (default is Enabled, settings of Enabled, Disabled)
This option when enabled will shut off the PC when the mother board is over heated. No temperature is specified. Seems strange to me that it is the mother board temperature that is monitored, and not the CPU. You could try to disable this option to check if you can go above 75° C.
Those are the only options about temperature throttling of the CPU or any other component.
One interesting thing to note in the H/W Monitoring screen. Each fan header has an option called Critical Temperature. When the CPU temperature or whatever temperature the fan header is set to monitor reaches this temperature, the fan on that header will run at 100% or full speed. The default Critical temperature for every fan header is 80° C.
If the throttling temperature of the CPU is 75°C, setting Critical Temperature to 80° C by default does not seem to make sense. It should be 75° C, or less, perhaps 70°C. I suggest setting this option to 70° C at least for the CPU Fan, so it runs at 100% when the CPU temperature approaches 75° C. I'm still not certain if Ctcl is being monitored instead of Tdie, although AMD states Tctl is the correct temperature for fan speed control for the 1800X CPU. Nothing is said about the maximum CPU temperature. I have found statements on various websites that the Ryzen throttling temperature is 95° C, but never in something directly from AMD. That is why I still wonder what is correct.
https://community.amd.com/community/gaming/blog/2017/03/13/amd-ryzen-community-update
Your new CPU cooler should help you keep your 1800X cooler, below 75° C, so you may not need to change anything related to CPU throttling. The new CPU cooler might not touch the memory, but it will be close. You should be able to remove the heat spreaders on your memory without damage. My G.SKILL Trident Z and FlareX memory have temperature sensors that are read by HWiNFO64, and are always at ~30° C. That is in a large well ventilated PC case, but memory temperature should not be a major problem.
As PetrolHead said, you should check the VCore that is currently set in the UEFI/BIOS for the CPU. The Auto default value is always more than is necessary, and increases the CPU temperature. At stock clock speeds of an 1800X, you should be able to use 1.3V or less for the VCore. The Auto VCore can be as high as 1.5V.
Subject: AMD Ryzen 1800x CPU thermal throttling
Posted: 15 Oct 2017 at 9:47am
I have these temperature related throttling options in the UEFI/BIOS of my X370 Killer SLI/ac board. I'm not sure if your board's UEFI will have these screens and options:
Advanced\AMD CBS\Zen Common Options\Custom Pstates / Throttling:
Relaxed EDC Throttling (default value Auto, settings of Auto, Enabled, Disabled)
According to this option's description, when set to Disabled, full throttling protection is enabled.
Enabled means reduce the amount of time the processor will throttle.
Auto is AMD recommendation, which is the same as Disabled. So the default setting is full throttling enabled.
So it seems if you set this option to Enabled, the processor will throttle less, which I assume means it allows a higher CPU temperature.
H/W Monitor:
Over Temperature Protection (default is Enabled, settings of Enabled, Disabled)
This option when enabled will shut off the PC when the mother board is over heated. No temperature is specified. Seems strange to me that it is the mother board temperature that is monitored, and not the CPU. You could try to disable this option to check if you can go above 75° C.
Those are the only options about temperature throttling of the CPU or any other component.
One interesting thing to note in the H/W Monitoring screen. Each fan header has an option called Critical Temperature. When the CPU temperature or whatever temperature the fan header is set to monitor reaches this temperature, the fan on that header will run at 100% or full speed. The default Critical temperature for every fan header is 80° C.
If the throttling temperature of the CPU is 75°C, setting Critical Temperature to 80° C by default does not seem to make sense. It should be 75° C, or less, perhaps 70°C. I suggest setting this option to 70° C at least for the CPU Fan, so it runs at 100% when the CPU temperature approaches 75° C. I'm still not certain if Ctcl is being monitored instead of Tdie, although AMD states Tctl is the correct temperature for fan speed control for the 1800X CPU. Nothing is said about the maximum CPU temperature. I have found statements on various websites that the Ryzen throttling temperature is 95° C, but never in something directly from AMD. That is why I still wonder what is correct.
https://community.amd.com/community/gaming/blog/2017/03/13/amd-ryzen-community-update
Your new CPU cooler should help you keep your 1800X cooler, below 75° C, so you may not need to change anything related to CPU throttling. The new CPU cooler might not touch the memory, but it will be close. You should be able to remove the heat spreaders on your memory without damage. My G.SKILL Trident Z and FlareX memory have temperature sensors that are read by HWiNFO64, and are always at ~30° C. That is in a large well ventilated PC case, but memory temperature should not be a major problem.
As PetrolHead said, you should check the VCore that is currently set in the UEFI/BIOS for the CPU. The Auto default value is always more than is necessary, and increases the CPU temperature. At stock clock speeds of an 1800X, you should be able to use 1.3V or less for the VCore. The Auto VCore can be as high as 1.5V.
superannoyed wrote:
