Using an Intel X Series Processor for 24/7 server

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I have just bought an ASUS X299 Pro motherboard, which I’m planning to use to build a larger 24/7 Proxmox hypervisor as an upgrade from my current Dell OptiPlex 5080 SFF. I’m planning to run the following:

• OPNsense/pfSense with a NIC passthrough
• TrueNAS with SATA or HBA controller passthrough
• A media server with an NVIDIA Quadro GPU passthrough
• A dozen mixed 2.5" and 3.5" HDDs
• Some VMs for testing

What worries me is the power consumption of the Intel Core X-series processors. I haven’t found anything concrete online about their real-world power usage, but I want to buy a processor with as many cores as possible without having excessively high power draw. You can find the list of processors and a comparison chart at the links below:

https://www.intel.com/content/dam/s...essors/core/intel-core-x-comparison-chart.pdf
https://www.intel.com/content/www/u...es/123588/intel-core-x-series-processors.html

The processor I’m looking at is the i9-10940X, launched in Q4 2019. Since it’s a 10th-generation chip, I’m hoping it will be cooler and more efficient than the 7th-generation i9-7940X.

I just wanted to check what’s actually possible or recommended. Specifically, can any of the following be done effectively on X299 CPUs?

• Lowering the CPU multiplier to reduce power
• Undervolting the CPU
• Adjusting PL1/PL2 power limits
• Lowering the mesh/uncore ratio
• Using C-states or other power-saving features

There are lots of posts and discussions about overclocking these CPUs, but I’m interested in underclocking the processor by undervolting the core voltage and reducing the CPU multiplier to save power.

Can anyone confirm whether these options work on X299, which ones actually help, and what wattage I should expect? Thanks!