The ASUS PRIME B550M-A delivers PCIe 4.0 with chipset-routed expansion

What PCIe slots are present on the ASUS PRIME B550M-A?

The PRIME B550M-A follows the standard B550 PCIe layout. The primary x16 slot runs at PCIe 4.0 x16 straight from the CPU — that’s Gen 4 for your GPU. A second x16 slot drops to PCIe 3.0 x4 through the chipset, and two PCIe 3.0 x1 slots handle smaller add-on cards. It’s the same sensible split you see on most B550 boards: Gen 4 where it counts, Gen 3 everywhere else.