9950X3D Undervolt, AI Cache Boost, FPS Boost Guide
Tip/Guide:
Cinebench R23 – BIOS Settings - AI Cache Boost
PBO = Precision Boost Overdrive
Standard = 73°C → 40.4K Points
PBO (Auto → Enabled) = 95°C → 42.9K Points
PBO Enabled + Curve Optimizer -30 = 83°C → 44.1K Points
Just -30 Curve = 73°C → 42.9K Points
Single-Core -30 Curve = 2265 (Not a big difference between CPUs I noticed, so no problem for gaming)
Specs: Asus X670E-E / 4090 / Ryujin 360 AIO / D.O.C.P "enabled", RAM 6400MT/s / Monitor 3840x2160
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*EDIT:
You can SKIP enabling "PBO".
Just do the "Curve Optimizer" and the "AI Cache Boost".
I tested PBO at "Auto" and "Enabled" and saw not really a big difference in games. The AI Cache Boost is what really provides the crazy FPS increase.
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[YOU NEED THE NEW BIOS UPDATE, CHECK IF "AI CACHE BOOST" IS MENTIONED IN THE BIOS UPDATE FOR YOUR MOTHERBOARD]
[Works probably on the 7000X3D Series AMD CPU's too.]
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START OF GUIDE:
Enter the BIOS and navigate to AI Tweaker → Precision Boost Overdrive:
• Go to "Precision Boost Overdrive".
• Search for "Curve Optimizer" and select "All Cores" -> "Negative".
• Set the values to -15 / -20 / -25 / -30 (depending on whats stable for you).
Test which setting works best for you.
It’s IMPORTANT NOT TO GO BELOW -30 - the lower the value, the more unstable the system might become.
However, the more negative the curve, the cooler the CPU runs and the more performance is possible.
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\**Extremely beneficial in games****
AI Cache Boost / Universal Game FPS Boost (+30-40-50 FPS) [YOU NEED THE NEW BIOS UPDATE]
• Open BIOS: Press [Del] or [F2] during startup.
• Navigate to AI Tweaker: Find the "AI Tweaker" menu.
• Change the setting: Set "AI Cache Boost" from "Auto" to "Enabled".
• Save & Restart: Press [F10] to save and restart your PC.
Enjoy a universal game FPS boost.
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***IMPORTANT**\*
RUN A STRESS TEST WITH AIDA64 OR AND WITH CINEBENCH R23/24 AND CHECK YOUR TEMPS WITH HWINFO OR WITH THE PROGRAM YOU TRUST AFTER ALL THESE SETTINGS!!!
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*EDIT: [Final Review]
I removed Scalar because it's not really beneficial. I read through multiple posts stating that it can degrade the CPU faster, but only at extreme levels like x6, x8, or x10, where it significantly increases voltage, heat, and long-term wear. The performance gains are minimal, so I removed it.
Also, PBO (Precision Boost Overdrive) isn’t that beneficial on its own—it mainly removes power limits, allowing the CPU to boost higher if cooling allows, but it increases heat and power draw without always providing a noticeable performance boost.
Instead, the "Negative" Curve Optimizer is far more effective. By applying a negative offset (-15 to -30), the CPU runs cooler, uses less power, and can maintain higher sustained boost clocks if stable.
I noticed AI Cache Boost (L3 Cache optimizations) is important, as it can improve performance in latency-sensitive workloads like gaming.
Overall, focusing on Curve Optimizer (Negative) and AI Cache tuning while avoiding unnecessary PBO and Scalar tweaks is the best balance of performance, efficiency, and longevity.
Pic 1 = AI Cache Boost \"auto\"
Pic 2 = AI Cache Boost \"auto\"
Pic 3 = AI Cache Boost \"auto\"
Pic 4 = AI Cache Boost \"auto\"
Pic 1.1 = AI Cache Boost \"enabled\"
Pic 2.2 = AI Cache Boost \"enabled\"
