Question - PCIE x8 into a PCIE x4

What is the maximum read and write speed for pcie x4 slots? pcie 3 0 x4 slot If any of the PCI Express slots could be considered a “sleeper”, it's probably the x4 slot The x4 slot is largely relegated to upgraded versions of x1 pcie x32 slot Expando Duo E416 Embedded Fanless Mini PC with i7 Skylake-S and PCI Express x16 slot and PCI Express x4 Slot

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