Coffee Lake, Plundervolt and the new CA microcode performance/uncore issues

[MDib]

Hello,

The new CA microcode released to fix Plundervolt is the worst microcode to date yet. I cannot speak for all CPUs, but for my 8700K and the people that were able to confirm the findings. So, the issues:

• Uncore/Ring was changed from 44x (max) to 43x, why?
• performance dropped in most benchmarks quite dramatically. In Cinebench R15 there's about a 5% perf drop at stock (1455 vs 1405 after CA microcode). Other benchmarks are also affected, Cinebench R20 as well.
• the performance drop remains when the CPU is overclocked, 1672 CB before, 1620 CB after CA microcode, for 5GHz OC.

I thought this was supposed to fix a SGX related vulnerability, yet turning off SGX completely in BIOS does nothing to alleviate these issue.

There is no way to turn this vulnerability patch off either, like it was the case with the Spectre/Meltdown fixes - other than reverting to older firmware and being stuck with older Intel RST/Intel MEI EFi modules.

This is the response I received from MSI support, which confirms the Intel microcode is what caused these issues, not their BIOS settings.

"About bios v1.9, we have consulted the relevant department, we are really sorry, in order to improve the overclocking stability of some CPUs, we have changed the option CPU Lite Load setting from Mode 11 to 17, about the offset option, you can adjust the Mode back to 11 in BIOS for a try. About the CPU Ring Ratio, it is changed by the new Intel Microcode, it may also affect performance in software, if you need the 4400Mhz, please manual adjust the option in BIOS. Sorry for any inconvenience caused."

Can we have a proper microcode update that fixes these things? One that we can turn off in Windows maybe, so we can keep updating the BIOS and receive updated IMEI/IRST modules?

Thank you.

[Alberto_R_Intel]

MDib, Thank you for posting in the Intel® Communities Support.

In order for us to provide the most accurate response to your inquiry, we will do further research on this matter, as soon as I get any updates I will post all the details on this thread.

Regards,

Alberto R.

Intel Customer Support Technician

A Contingent Worker at Intel

[MDib]

Thank you Albert,

Please let me know if more information is needed. There is also a Reddit thread on this issue, and a MSI forums thread as well. I will link them below, the MSI forum thread contains images with bench scores as well as the lowered Uncore/Ring multiplier. Again, if I can be of assistance with further info, please let me know.

https://www.reddit.com/r/intel/comments/esbgmr/new_intel_0xca_microcode_kills_cpu_performance/

https://forum-en.msi.com/index.php?topic=330834.0

[Alberto_R_Intel]

Hello MDib, I just received an update on this matter.

Thank you very much for sharing your feedback, for Intel® it is very important the suggestions and recommendations provided by our customers, that is why we will send your comments to the proper department in order to continue working will all the manufactures and coming out with all these improvements.

Just to let you know, if you would like to share your feedback directly you can always send your comments to secure@intel.com.

In the meantime, Intel® recommends contacting the OEM (Original Equipment Manufacturer) and have his drivers, Firmware, Operating System and BIOS updated under the OEM recommendations.

In reference to the overclocking subject, Intel® does not make comments on that matter, actually, we recommend having everything in default settings, since altering clock frequency or voltage may damage or reduce the useful life of the processor and other system components and may reduce system stability and performance. Product warranties may not apply if the processor is operated beyond its specifications, so we suggest to check with the manufacturers of system and components for additional details about overclocking.

Any questions, please let me know.

Regards,

Alberto R.

Intel Customer Support Technician

A Contingent Worker at Intel

[MDib]

• not ONE word on the actual performance impact
• not one word on why the default Uncore/Ring multi was modified from 44x to 43x.

We might just be ordinary customers, but we're still smart enough to detect vague PR speak that doesn't contain any useful information.

My CPU is not overclocked, by the way. Intel sells unlocked CPUs, it's a feature that you pay extra for. We should really not try to make it like it's unintentional.

Myself and many other enthusiasts build our own PCs, not to be limited by the bad hardware choices from some OEM or their BIOS limitations.

So, can we actually get a proper microcode that returns the Uncore/Ring to its 44x multi defaults? Can we have a way to turn off these mitigations inside the OS, like it's possible with Spectre and Meltdown?

Or will we have to just keep adding layer upon layer of performance reducing microcodes? Just today a new vulnerability was disclosed.

It's getting a bit tiresome.

[Alberto_R_Intel]

Hello MDib, I just received another update on this matter.

In regard to this topic, we just wanted to let you know that we understand your frustration and we are also taking into consideration all the feedback provided on this thread.

Intel® has provided system/motherboard manufacturers with the necessary firmware and software updates to resolve the vulnerabilities.

These vulnerabilities will not stop in a short time or maybe never but the good thing is that Intel® will not stop either sending alerts, helping the OEM (Original Equipment Manufacturer) to create the patch and the necessary tools to attack them.

So please work closely with your OEM to keep your system always update and following his instructions before you updated any software/driver and if need it the OEM will work with Intel® in this specific matter/Vulnerabilities.

Any questions, please let me know.

Regards,

Alberto R.

Intel Customer Support Technician

A Contingent Worker at Intel

[orocoke33]

On the alternative hand, ought to you please make clear the system which you have accompanied to obtain the tool associated with this example? Could you please inform us if the affected layout has been developed throughthis pageor a 3rd-celebration business enterprise?