Intel Raptor Lake 0x129 CPU Microcode Performance Impact On Linux

Motherboard vendors have begun releasing updated BIOS versions for Intel Core 13th/14th Gen motherboards that offer the new "0x129" CPU microcode that is intended to address the Raptor Lake stability issues that have been causing instability problems and crashing errors for a growing number of Intel Core 13th/14th Gen processors. Intel reported in their (Windows) testing that the 0x129 CPU microcode should offer negligible performance impact but I was curious to run my benchmarks under Linux of this new CPU microcode.

At the end of the week multiple motherboard vendors have begun releasing updated BIOS versions that incorporate the Intel 0x129 CPU microcode for Raptor Lake / Raptor Lake Refresh processors. ASUS has been among those vendors and they have published beta versions already for nearly their entire portfolio of Raptor Lake (Refresh) motherboards. Over the weekend I conducted some preliminary Intel 0x129 microcode benchmarks on an ASUS PRIME Z790-P WIFI motherboard and Intel Core i9 14900K processor.

These benchmarks were looking at the "pre" performance using the 1661 BIOS with its 0x125 CPU microcode and then repeating the same benchmarks after upgrading to the ASUS 1662 BIOS with the new 0x129 CPU microcode for addressing the Raptor Lake stability issues. No other changes were made to the system hardware/software between the pre and post benchmark and all of the BIOS settings were kept to the same values on the former and new BIOS versions.

This is just the first installment of testing at Phoronix for the Intel 0x129 CPU microcode and depending upon reader interest level and if I encounter any peculiarities on any other Raptor Lake motherboards and processors, further tests may be published.

On a geo mean basis for 188 benchmarks run, the performance overall was flat from this new BIOS / CPU microcode... For the most part the performance was the same but there were some exceptions observed... Continue reading.