Intel Core 13th and 14th Gen Vmin Shift Instabilty Update - New Microcode Update (0x12F)

[Thomas_Hannaford]

As part of its effort to continually improve its products, Intel is releasing a new microcode update (0x12F) supplementing the 0x12B microcode update released in September 2024. This new microcode further improves system conditions that can potentially contribute to Vmin Shift Instability on Intel Core 13th and 14th Gen desktop-powered systems. Intel is releasing this 0x12F update based on Intel’s investigation of a limited number of reports regarding systems continuously running for multiple days with low-activity and lightly-threaded workloads.​

The release of the 0x12F microcode does not alter the root cause determination for the Intel Core 13th and 14th Gen desktop processor Vmin Shift Instability issue: https://community.intel.com/t5/Processors/Intel-Core-13th-and-14th-Gen-Desktop-Instability-Root-Cause/m-p/1633442​

Based on microcode testing and validation, Intel has identified no measurable performance impact with the 0x12F microcode update*.​

Intel continues to recommend users with Intel Core 13th and 14th Gen desktop processors ensure they have the latest BIOS updates installed and utilize the Intel Default Settings profile in their BIOS to mitigate Vmin Shift Instability risk with their systems.

Small Print:

*Intel’s internal testing comparing 0x12F microcode to 0x12B microcode – on Intel® Core™ i9-14900K with DDR5 5600MT/s memory- indicates performance impact is within run-to-run variation (i.e., Cinebench R23.200, Speedometer 3, WebXPRT4 (v3.73), and Crossmark)**. For gaming workloads on Intel® Core™ i9-14900K with DDR5 5600MT/s memory performance is also within run-to-run variation (i.e., Shadow of the Tomb Raider, Cyberpunk 2077, Hitman3: Dartmoor, Total War: Warhammer III – Mirrors of Madness)***. System performance is dependent on configuration and several other factors.

**Processor: Intel® Core ™ i9-14900K, Motherboard: Intel Raptor Lake Reference Board (M40919-101), Memory: 64GB at 5600MT/s, Storage: Samsung* MZVL2512HCJQ-00A00, Graphics: Intel® UHD Graphics 770, Graphics Driver Version: 32.0.101.6314, Display Resolution: 1280x1024, Operating System: Windows 11 (version 26100.2161)

***Processor: Intel® Core ™ i9-14900K, Motherboard: OEM board, Memory: 2x16GB at 5600MT/s, Storage: Samsung* MZVL2512HCJQ-00A00, Graphics: MSI* RTX 4090 Suprim X, Graphics Driver Version: NVIDIA* v572.16, Display Resolution: 1920x1080, Operating System: Windows 11 (version 26100.2161)

[Vortan]

Is there any way of upgrading the microcode to 012F if the manufacter doesn't release a bios upgrade for the motherboard ? 

Maybe via a batch file ?

Owner of a Z690 MB running on 0x12B .

[HumbleDeer]

At your own risk, yes. You can swap out microcodes in the firmware package and flash it either using the built in software options if the firmware doesn't verify packages, or through the hardware chip interface if it does. It's not something for a beginner. 

[iameatingjam]

There's also a software method. Doesn't look like 0x12F has been prepared yet, but I think there is enough info there for you to be able to do it yourself. Also don't worry even though its meant for laptops since they often get bios updates much less than desktops, it still works on desktops. It updates the ucode as soon as windows loads rather than on boot but, yeah, it definitely still works, just in a different way.

https://www.techpowerup.com/forums/threads/intel-how-to-update-your-microcode-for-intel-hx-13-14th-gen-cpus-laptops-mobile-easily.325403/

Also you could contact the guy. Seems very knowledgeable and also very helpful.

[iameatingjam]

The link I gave you before, this one:

https://shorturl.at/7LBzV

Its been updated with the most recent ucode. So with it already prepared, its a really simple procedure. Its explained in the post. You should be able to do it in <5 minutes.

I haven't done it myself, I'll just wait for the bios update. However, if you cannot do that for whatever reason or are just very cautious and want it applied asap, this is an option.

Like I said the ucode will get loaded with windows rather than at boot.

[EliTeAP]

Will be looking out for an update on my Z790-E Strix then.

Recently moved to the 14900K and have had some wierd hiccups now and then (even with P1 and P2 253W limit)

Other than that, always been a happy owner of Intel processors.

[Adamkcmo]

If you are experience some weird issues, try Xtu and drop the P cores to 5.4

I had the horrible luck of a bad 13900k after 1 year of consistent crashing.

I submitted an RMA and was upgraded to 14900k I still have those hiccups and downclocking is the only thing that resolved the issue. 

I was checking also for the new Z790 E bios update hoping I could extend the life of my CPU not wanting to submit another RMA.

Hope that helps since we have similar build

[ZjAlic]

Hello,

I have updated my motherboard with the latest BIOS, which includes the microcode update 0x12F. After initial testing, I have some negative feedback.

Why? Because with the previous microcode, I was able to optimize my 14900K quite well by undervolting it—improving its performance without overclocking. As a result, it ran cooler, faster, with lower voltage, and less heat dissipation.

Now, it's the opposite. I can no longer undervolt it, so it runs at higher voltages, produces more heat, has lower performance and most likely has a reduced lifespan.

Could you please explain how I’m supposed to trust Intel again when updates break what previously worked?

[PC1997]

Check and make sure undervolt protection is disabled in the bios. Most likely it was re-enabled when you updated the BIOS.

[ZjAlic]

I have checked this option and tried both disabled and enabled and this option is working fine from BIOS perspective, but now on OS level is overriden completely which is even worse! Intel does not want us to play with undervolting at all!

[PC1997]

Try disabling CEP if you haven't already.

[TREACHER0US]

Allow us to uninstall whatever was overwritten and revert back to previous BIOS version.

[TREACHER0US]

I'm having the same issue with my 14900k on the ASUS Z790i motherboard. I reverted to the previous BIOS version and I'm still experiencing the same problem. Something was overwritten and now my CPU thermal throttles with my undervolt settings.

[PC1997]

"For those unaware, on ASUS ROG motherboards in the UEFI BIOS under Tweakers Paradise you'll find an option to revert to an older CPU microcode.

One reason you may wish to utilise this is due to Intel's Undervolt Protection (UVP) in later microcode causing the CPU to disregard undervolt requests."

If your motherboard supports this feature, you can load an older microcode and see if that is the cause. I would not load any microcode prior to 0x12B. And disabling UVP/CEP should allow you to obtain the same results without having to load an older microcode anyways.

As always, do this at your own risk.

[ZjAlic]

I can conclude the following:

1. After BIOS upgrade and restart on 14900K with ASUS motherboard with z790 chipset, with Intel Extreme profile as default and all other settings on default , CPU voltage goes beyond 1.5V, which is critical and dangerous for long use.

2. The new microcode 0x12F does override BIOS setup as soon as it loads into OS e.g. Windows for options such as undervolt protection or cpu offset voltage, has no effect with all these settings enabled.

3. You can not revert microcode on CPU even if you flash older versions of BIOS 

4. My14900K with correct undervolting outperform 14900KS, now with any combination in BIOS/OS it's not possible.

5. Intel should support users to allow undervoltage as it does not harm CPU, instead it prolongs its life and CPU perform way better, that is most likely not Intel's interest.

6. Most likely Intel knows all above but they don't care about users , they care only about profits, but millions of users will read this and if they don't do something the profit will drop radically anyhow. 

[PC1997]

1. DO-NOT-USE the Extreme power profile. 100% your CPU will degrade over time if you use it. The latest microcode update (0x12F) is only a minor revision and will not change this reality if you use this power profile.

I understand it is one of three power profiles available: Baseline, Performance and Extreme. You should be able to use any of them, but the reality is Intel should no-longer be recommending its use. It was originally created for the KS SKU chips ONLY. The reality: K /KS are the exact same silicone other than the latter being a higher binned chip and the thinking was it should be able to handle more power... This is false. ASUS should not be setting anything other than the Baseline power profile by default. This goes for any other motherboard vendor as well. However, this SHOULD be an option available, simply not by default. This way users can degrade their processors at their own risk.

2. Not all motherboards allow you to revert to an older microcode. Other settings may be changed or previously available and now locked out by the decision of motherboard vendors as well.

3. It is recommended users post on the forums corresponding to their motherboard brand for help with undervolting or other setting corresponding to a particular model motherboard.

[TREACHER0US]

This actually worked! I was able to get my temps under control.

Thanks for taking the time to reply. This helped me out a lot.

[sMyAsiN]

Hello , A question! . .
Have there been any reports of instability and crashing issues with 13th and 14th generation processors on B600 & B700 and H600 and H700 series motherboards? And could 13th and 14th generation processors be vulnerable to the recent crashes and crashes with these motherboards?

I would be happy to answer and comment on my topic:

https://community.intel.com/t5/Mobile-and-Desktop-Processors/The-story-of-13th-and-14th-generation-processors-and-my/m-p/1692248#M84059

[kw001]

Yes one can update the microcode in a diy manner if you do not want to wait for microsoft to integrate it into Windows, which will happen eventually, same for Linux distros. Both Kernels have a microcode loading mechanism which is actively used. Becausee of this, installing the VMWare Microcode loading driver shown in the linked "techpowerup" thread, is not a good idea. As the name suggests its intended for virtual machines.

If you want to update the code in the BIOS of your system there are 2 steps involved:

1. modifying your Firmware (replacing the microcode)

2. flashing it into the flashrom of your system

Step 2 can be done with software provided by your system vendor sometimes even integrated in your system setup or via an external program. It so happens that some vendors checksum their firmware files before flashing. A modified file will then be rejected. Asrock does that. Then you havee to flash it by other means. Many BIOS vendors provide toolchains for that, AMI for instance has a tool to flash from Windows.

Step one can be done also by tools from BIOS vendors, MMTool comes to mind but there are also free tools´to swap the microcode. The UBU contains a toolchain for that.

Regarding the 0x12F microcode i can not see any adverse effects on my 13900k on z790 regarding its undervolting behaviour compared to the previous microcode. But i can confirm weird UEFI behaviour without a complete reset, which is why i would recommend after flashinga a different firmware to always reset the firmwaresetup  to default values, save and coldstart before a complete reconfiguration of the setup. Most firmwares are also riddled with bugs that manifest to murphies law in such situations and will be confounded with the microcode swap.

I would also recommend to always check that "auto" values are set by the firmware to allowed values, unfortunately that is frequently not the case. And in dangerous areas i would recommend to do without them and set the values myself. Its tedious but rewarded with a stable system. Look at intels specs and set the values accordingly for instance the power limits and max current. The Intels "max values" are there for a reason, some they even describe in the specs.

Additionally I would recommend to leave all protective measures active, for instance the CEP, and tune instead by a combination of DC/AC LL and undervolting and carefully testing the settings for stability. The nvidia driver installer is a good test for that, it will most times not complete on an unstable setting.