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Request: Video guide on LLC tuning for X99 when undervolting Xeon E5-26xx v3 (with S3Turbo & settings bios) #190

@NumpaMC

Description

@NumpaMC

Hello miyconst,

I would like to request a detailed video guide (or technical explanation) about tuning Load-Line Calibration (LLC) on X99 motherboards when undervolting Xeon E5-26xx v3 CPUs.

Context

I'm currently running a Xeon E5-26xx v3 system on an X99 board.
I use:

Undervolting via BIOS (manual voltage mode)
Microcode modification (optional depending on scenario)
S3TurboTool for turbo unlock on v3 CPUs
When undervolting aggressively, I encounter a problem:

Under load transitions (especially AVX or sudden current spikes), voltage sometimes overshoots instead of staying stable.
Or LLC settings cause large transient spikes, which defeats the purpose of undervolting.

What I would like explained

How LLC levels on X99 actually behave electrically
Why some LLC levels increase transient overshoot
Relationship between Vdroop, overshoot, and transient response
Safe LLC strategy when undervolting Xeon v3
Which LLC range is ideal?
Should we prefer slight Vdroop instead of flat-line voltage?
Interaction between:
S3Turbo (all-core turbo unlock)
BIOS voltage settings
VRM behavior on OEM / Chinese X99 boards
Recommended testing method:
Proper stress tests (AVX / non-AVX comparison)
Monitoring transient spikes (HWInfo / oscilloscope insight if possible)

Why video would help

Many X99 users (especially with turbo unlock) struggle with:
Random freezes under load
Voltage jumping unexpectedly
Instability when undervolting too far
A visual explanation of LLC waveform behavior would help the community a lot.

If possible, a comparison between:

LLC Level 1 vs Level 3 vs Level 5 (example)
Undervolt + Turbo Unlock ON vs OFF
would be extremely valuable.
Thank you for your work on Xeon turbo unlock tools 🙏

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