MSI has acknowledged a long-running issue affecting some of its AM5 motherboards, where certain graphics cards don’t always run at the PCIe speed and lane width they’re supposed to. In response, the company has started rolling out a BIOS fix, beginning with the MSI MAG X870 Tomahawk WiFi.
The problem itself is frustrating because it can appear randomly, most often during cold boots. Users have reported situations where a GPU that should link at PCIe 5.0 x16 instead starts up at a reduced mode such as PCIe 5.0 x8. In more severe cases, some systems have shown GPUs dropping all the way down to PCIe Gen 2.0 or Gen 3.0, which can significantly hurt performance on modern NVIDIA and AMD graphics cards.
While similar behavior has been mentioned by users on a few motherboards from other brands, the reports have been especially common on MSI AM5 boards, leading to widespread discussion across community forums. Some users also noticed unusual workarounds, like manually turning off the power supply before a cold boot, after which the system would sometimes initialize the GPU properly at PCIe 5.0 x16.
According to reports, MSI worked to reproduce the bug across multiple configurations and eventually traced it to a specific mix of components and firmware—essentially a “motherboard + BIOS + AGESA + CPU + GPU” combination that could trigger the PCIe link to initialize incorrectly or become “locked” into a lower mode.
To address it, MSI has released BIOS version 7E51v1A81 for the MAG X870 Tomahawk WiFi. This update includes AMD AGESA PI Pre-13.0.0 microcode and is designed to mitigate the PCIe mode lock behavior that causes GPUs to run below their intended PCIe generation or lane configuration.
For now, the updated BIOS appears to be available only for the MSI MAG X870 Tomahawk WiFi, but it’s expected to expand to other MSI AM5 models. The issue has been reported across both 600-series and 800-series boards, and some users claim the AGESA 1.2.0.3 branch made the behavior more noticeable. Early feedback on the new BIOS is mixed, with some users reporting the fix worked and others seeing little to no change—suggesting results may still depend on the exact hardware combination involved.
If you’re experiencing unexpected PCIe link speeds or reduced lane width on an MSI AM5 system, keeping an eye out for BIOS updates for your specific motherboard model may be the most practical step, especially if your GPU performance seems lower than it should be after a cold boot.
