Motherboard · medium

How to fix PCIe generation - speed mismatch

Error code: PCIE-GEN-MISMATCH

What this error means

GPU or NVMe SSD running on PCIe 3.0 instead of PCIe 4.0/5.0, performance is significantly reduced. Reports of PCIe generation - speed mismatch usually describe a sudden crash, brief unresponsiveness, or a stop-code screen appearing out of nowhere.

Updated

Before you begin

Save open work and back up important files. Use instructions for your exact device and software version. If Windows cannot start, see the startup guide.

Work through these checks

0 of 3 complete
01Set PCIe slot to Auto or Gen4 in BIOS
  1. Set PCIe slot to Auto or Gen4 in BIOS
What to expect

Check whether the original symptom still occurs.

If it does not help

Continue only if this check applies to your device. Consult its manufacturer if you are unsure.

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02Move the GPU to the primary PCIe x16 slot
  1. Move the GPU to the primary PCIe x16 slot
What to expect

Check whether the original symptom still occurs.

If it does not help

Continue only if this check applies to your device. Consult its manufacturer if you are unsure.

Browse related errors
03Verify GPU speed with GPU-Z Bus Interface tab
  1. Verify GPU speed with GPU-Z Bus Interface tab
What to expect

Check whether the original symptom still occurs.

If it does not help

Continue only if this check applies to your device. Consult its manufacturer if you are unsure.

Browse related errors

Possible causes

  • The CPU or board does not support the higher generation PCIe
  • GPU in secondary slot which is limited to PCIe 3.0 x4
  • Incorrect PCIe settings in BIOS (Gen 1/2/3 instead of Auto)

Useful Windows tools

These commands open Windows tools. Review changes before applying them.

dxdiag