Using x16 PCIe slot preventing lower package C states

[rudigualte154702d5]

Hi Community,

Motherboard: MSI PRO Z690-A DDR4
Processor: Intel Core i5-12400
OS: Ubuntu 22.02

I am experiencing an issue with my MSI motherboard related to the x16 PCIe slot (PCIe Slot 1, which connects directly to the CPU) preventing low package C states (ASPM) when used with an ASM1166 SATA controller.

Issue Details:
- When using the ASM1166 SATA controller in the x16 PCIe slot (PCIe Slot 1), the CPU cannot go to lower package C states (only reaching C2 state).
- In contrast, using the same PCIe card in a chipset-connected PCIe slot allows the CPU to reach C6 state without any problems.
- This issue only occurs with the PCIe slots linked directly to the CPU, not the chipset-connected slots.

BIOS Configuration:
- I have set all ASPM features to enabled in the BIOS including PEG and Ports to L1.
- Checking the ASPM status on the OS shows everything is enabled:
sudo lspci -vvv | grep "ASPM .*abled"
LnkCtl: ASPM L1 Enabled; RCB 64 bytes, Disabled- CommClk+
(repeated for each PCIe link)

Intel Support Insight:
Intel support provided the following potential solution for this issue:
"In your BIOS:
Advanced -> Admin -> Chipset -> System Agent (SA) Configuration -> PCI Express Configuration
Set Multi-VC to Disabled on both of PCIE Root Port 1 & PCIE Root Port 2.
Setting Multi-VC to Disabled could help reaching C10, meanwhile, by being enabled, the system can only reach C2."

Problem:
However, the MSI BIOS does not have an option similar to "Multi-VC" to disable on the PCIe Root Ports.

Could you please provide me any guidance that addresses this issue?

Thank you for your support.
Best regards,

 

[Svet]

Check PM

 

[eseed158902e1]

Hi interested in enabling this too on an h610m board due to 16x slot preventing anything lower than c3, is there a solution? Thanks!