KurtFuchs
commented
3 months ago Just as a quick update, it seems that the FSP setting does work and does not require any logic on the coreboot side. I tested it with a quick
for (int i = 0;i < 5;++i)
{
params->VrVoltageLimit[i] = 200;
}and can confirm that the max. clock i get (yes, it seems to still boot, albeit very slow) is 800MHz with very low temperatures. Sadly i cannot get voltage readout working under Linux, i will edit this post and add the readout voltages if i have found a solution to this, as i do currently have no oscilloscope at hand.
The problem you're addressing (if any)
As Intel has pretty much shipped flawed microcode up until now (well, lets hope they fixed it) that kills CPUs from 13th and 14th Gen, even without OC, i wanted to ask if it would be possible to a.) update to the newer microcode once it is available and b.) maybe provide a setting in EDKII to set a VR Voltage limit. The BIOS Versions delivered from Asus, Gigabyte etc.. apparently only apply the VR Voltagecap of 1.5V, if the Intel Default Settings are loaded. If you use other settings, this Voltage cap gets removed. (Video from Buildzoid that shows voltage behavior).
Describe the solution you'd like
I was wondering if Coreboot does apply said Voltage cap when loading the 0x129 Microcode. I looked at the Intel FSP Repository and found the setting that also gets recommended in the linked Video (although there AMI is used), called VrVoltageLimit in the FspsUpd Header File. Now i do not know if there is more logic needed on the coreboot side to activate the limit or not.
Where is the value to a user, and who might that user be?
The value would be a stable CPU that does not degrade over (short) time.
Describe alternatives you've considered
No response
Additional context
No response