Does Alder Lake support disabling PCIe Spread Spectrum Clocking (SSC)?

[bcatt]

Does Alder Lake support disabling PCIe Spread Spectrum Clocking (SSC)? The BIOS provides an option to do so (see attached) but setting it to "Disabled" has no effect. Even after setting the option to disabled, SSC is still enabled. 

I have seen it reported elsewhere that it is difficult to turn off SSC. In a discussion thread for a different processor (Apollo Lake), Intel notes "Disabling SSC in Apollo Lake is not supported / not POR (Plan of Record), not validated and not recommended."

Can you please confirm that it is possible to disable SSC on Alder Lake? 

[Alberto_R_Intel]

bcatt, Thank you for posting in the Intel® Communities Support.

We will be more than glad to assist you with this matter. 

In reference to this scenario and in order to provide the most accurate response to your inquiry about Alder Lake support disabling PCIe Spread Spectrum Clocking (SSC), we will do further research on this matter to gather all the information about this topic. 

For us to be able to do that, we just wanted to confirm if there is any specific Alder Lake processor model that you are interested in finding those details?

Any questions, please let me know.

Regards,

Albert R.

Intel Customer Support Technician

[bcatt]

Thanks. We're using the Core i9-12900E.

[Alberto_R_Intel]

bcatt, You are very welcome, thank you very much for confirming that information.

I just transferred this thread to the proper department. They will further assist you with this subject as soon as possible.

Regards,

Albert R.

Intel Customer Support Technician

[Diego_INTEL]

Hello @bcatt,

Thank you for contacting Intel Embedded Community.

I would say the same response as with the Apollo Lake. Also, recently I've been investigating this a lot, it seems that disabling this from the BIOS menu does nothing, this is happening in other families too, we will have to wait for future updates or you can try changing this from the ME configuration to see if it helps.

Best regards,

@Diego_INTEL 

[bcatt]

Diego,

Thanks. That's really helpful.

How would I go about changing this through ME? Can you say a bit more about this? 

Thanks,

@bcatt 

[Diego_INTEL]

Hello @bcatt,

You are very welcome and I can say that this can be done using the latest CSME for Alder Lake S, from the document #776314, but you will need a Premier account in order to get access to this document. There, you may find a guide that helps for this.

But yes, at least the BIOS experts are aware of this situation, we have to wait for a newer release, but this may be until next year.

Best regards,

@Diego_INTEL