It indicates that once the M.2_2 slot is filled, the SATA6G_56 component will no longer function.
It indicates that once the M.2_2 slot is filled, the SATA6G_56 component will no longer function.
Hello everyone. When examining new B550 motherboards, I noticed a specific note that helps clarify things. It seems the design limits certain configurations—like pairing some SATA ports with M.2 SSDs. If you have six drives (two M.2 and two SATA), you can still achieve full performance because of this setup. Your question is deeper: why does this happen? On the internet, PCIe and SATA are often confused, but they serve different purposes. The issue with your SATA ports being disabled in the X4 PCIe lane might be due to how the chipset manages lanes. SATA ports don’t necessarily have separate lanes, but their configuration affects performance. For more detailed insights, you might explore technical forums or manufacturer documentation beyond official sites.
They're interpreting the setup correctly. Ensure the two SATA SSDs and two SATA HDDs aren't placed on ports 5 and 6. This relates to the CPU and chipset's input/output connections. SATA and PCIE signals are distinct, but the chipset design limits the number of ports it can handle. Only a few connections fit on each lane, so they prioritize M.2_2 and SATA 5/6 together. This detail isn't widely shared, but checking the chipset block diagrams can clarify the routing process. A review by KitGuru discusses this on the B450's page: https://www.kitguru.net/components/mothe...-review/3/
When pairing an x16 slot with an m2 slot, the x16 is reduced to x8. The combined performance of the x16 GPU and x4 M2 together equals x20. Since there are no extra lanes, the reduction from x16 to x8 ensures compatibility, allowing the x8 + x4 configuration to function properly.
It was a B450 illustration, since I couldn't locate a similar block diagram for B550. I believe the specific example you mentioned doesn't apply to B550, as the top PCIE connector is distinct and will operate at x16 speeds. The bottom PCIE x16 slot does overlap bandwidth with other PCIE slots, which is evident from the image you shared.
I mentioned the B450 specs and did some calculations. Of course, the B550's top PCIe and M2 slots are distinct.