Hi Lars, list,
On Wed, Jul 15, 2020 at 5:41 PM Lars Hochstetter lars.hochstetter@fu-berlin.de wrote:
Update: I tried the https://review.coreboot.org/c/coreboot/+/42547/ on my T430 (i7-3840QM, Debian Buster 4.19.0-9-amd64) using coreboot v4.12 + SeaBIOS as base.
I used s-tui to track the CPU frequency.
Without the patch on coreboot v4.12 the CPU reached its "usual" 3.3 - 3.4 GHz (4C/8T) using the stress function of s-tui.
With the patch the CPU reached at most 3.2GHz (intel_pstate) / 2.8GHz (acpi-cpufreq).
Thanks for testing! I'm the one who made that change, and I currently only have two CPUs to test it with. I generally check the CPU frequency with: `cat /proc/cpuinfo | grep MHz`
Maybe there is an issue with mobile CPUs?
I'd say the issue is because of how I determine the overclocking headroom that the CPU is capable of. On my CPUs, it happens that the number of OC bins is the same as the number of steps between the base frequency ratio and the maximum turbo ratio. I imagine this isn't the case for other CPUs (which I do not currently have any of nearby) and would explain why the gains aren't as high as expected.
It would be nice if you could provide a few MSR values from that CPU. You can use `rdmsr` from msr-tools: https://github.com/intel/msr-tools
* 0xce (MSR_PLATFORM_INFO) * 0x194 (MSR_FLEX_RATIO) * 0x1ad (MSR_TURBO_RATIO_LIMIT)
On 24.06.20 20:00, Lars Hochstetter wrote:
Hi, thanks for the pointer!
I only fear that running my CPU at the maximum possible Turbo Ratio will overheat it.
I can give it a try but I'm actually looking for an option to limit the maximum Turbo Ratio the CPU is allowed to reach (hence the disabling of TurboBoost altogether).
In its current state, my patch seems to achieve that :P
On 21/06/2020 00:52, Evgeny Zinoviev via coreboot wrote:
Hi again. There's another patch that fits to the topic that you will probably want to try out: https://review.coreboot.org/c/coreboot/+/42547/
On 12/15/19 3:57 PM, Lars Hochstetter wrote:
Hi everyone,
I'm looking for an option to configure my Intel IvyBridge CPU (enable / disable Hyperthreading, TurboBoost, set configurable TDP level etc.) using coreboot / nvramcui. My board is a Lenovo Thinkpad T430. So far, "only virtualization" is configurable and can not be enabled / disabled "in flight" but requires a rebuild of coreboot.
Is anyone currently working on something similar?
Is anything planned in that regard?
Kind regards
lhochstetter
Thanks in advance,
Angel