Yesterday was our first look at the Intel Panther Lake Linux performance with the Core Ultra X7 358H and focused on the CPU performance. In today’s benchmarking is a look at the very exciting Xe3 graphics found with the top-tier Panther Lake models: the Arc B390 Graphics with 12 Xe cores.
The Intel Core Ultra X7 358H features the Arc B390 GPU with 12 Xe cores and up to 2.5GHz maximum graphics frequency. On the display side is eDP 1.5, DP 2.1, and HDMI 2.1 support with the ability to drive up to an 8K @ 60 resolution and up to four total displays.
The Xe3 graphics with Panther Lake are quite exciting as previously detailed. The Panther Lake graphics on Linux are in good shape with Linux 6.18+ and Mesa 25.3+ but ideally for best support for new hardware to always be using the latest code, which for the moment is Linux 6.19 and Mesa 26.0+. Plus with Linux 6.19 for the MSI Prestige 14 laptop is working WiFi and audio anyhow. Make sure you have a recent linux-firmware package installed on your system too for recent Intel GuC firmware for the Xe3 graphics.
While the OpenGL and Vulkan acceleration with Panther Lake were working with my testing on Linux 6.19 and Mesa 26.0-devel, at first I was struggling to see any performance uplift over Lunar Lake Xe2 graphics in my testing. A very frustrating experience with minimal gains over Lunar Lake. Intel recommended testing with the “performance” platform profile while all the other laptops were in the default / out-of-the-box “balanced” mode. At first I was told between the balanced mode on Microsoft Windows and balanced mode on Linux there can be up to a 15 Watt difference in the PL1 state. Then I was told the power limits were the same under Windows and Linux for this laptop, but that MSI programmed their balanced defaults lower than Intel recommends. Intel expects their OEMs to have higher PL1 minimum values for balanced mode but MSI set it lower at 15 Watts min and 30 Watts max for at least this laptop model. Typically I prefer testing in the default/out-of-the-box configuration (e.g. balanced mode) for representative of user experiences and typically the performance mode on laptops not being too significant for most models, but it appears the MSI firmware defaults are rather gimped. With this MSI Prestige 14 Flip AI+ being an Evo branded laptop, it’s surprising this passed Intel’s “Evo” requirements. Long story short, that’s why the performance run is used for this laptop and took longer time getting out these Linux benchmark results.
The recommended workaround is switching to the performance mode along with a temporary workaround for Thermald. In addition to Thermald, which is shipped by default on most modern Linux distributions, Intel also recommends having their Low Power Mode Daemon (LPMD) also enabled. The performance mode with Thermald workaround and manually installing LPMD in turn finally was then showing some competitive Xe3 graphics performance compared to the other laptops in their out-of-the-box balanced mode.
It is unfortunate that the out-of-the-box experience wasm’t cleaner for launch time nor clear in knowing about this up to 15 Watt difference between Windows and Linux default (balanced) modes until it was finally communicated to me. So early Panther Lake users be aware if you are finding disappointing out-of-the-box performance, especially for the MSI Prestige 14 laptop while we’ll see what other Core Ultra Series 3 laptop models may face similar challenges. There will likely be a follow-up article with more details as I await more clarification/answers from Intel regarding the default balanced mode behavior on Panther Lake.
So with that out of the way, let’s see how the performance and power are looking for the Arc B390 graphics with the Core Ultra X7 358H under Linux with the Mesa Git + Linux 6.19 stack across the board. The other laptops for comparison included:
Ryzen AI 9 HX 370 “Strix Point” – ASUS Zenbook S16
Core Ultra 7 258V “Lunar Lake” – Lenovo ThinkPad X1 Carbon G13
Core Ultra 7 155H “Meteor Lake” – Acer Swift 14
Core Ultra X7 358H “Panther Lake” – MSI Prestige 14
Core Ultra X7 358H “Panther Lake” – MSI Prestige 14 – Perf
The “- Perf” run is with the performance profile, Thermald workaround, and LPMD loaded on the Panther Lake system per Intel’s recommendations given the gap in TDP between Windows and Linux.
Sadly, no AMD Ryzen AI Max “Strix Halo” data for reference. As noted in the Panther Lake CPU benchmark article, with HP having requested the ZBook Ultra G1a Ryzen AI Max+ 395 review sample back after testing, I don’t have any Strix Halo laptop review hardware for comparison at the moment. With re-testing all the hardware each time — not to mention all the RADV ray-tracing improvements and the like in recent months — I am not able to provide any Strix Halo performance comparison data for this current Panther Lake B390 testing. Hopefully I’ll find my hands on some new Strix Halo laptop review hardware soon.
