pcie ssd in slot : rbuildapc

Yes, PCIe is backwards compatible as long as the item fits it The main issue is the slot is slower than the so it won't be as fast as

2 PCIe SSD Host Adapter can not splitter PCIE X8 to PCIe X4X4, so your motherboard must support PCIE Bifurcation function Otherwise, only one NVMe SSD will

m2 pcie 40 in 30 slot You're referring to NVME based M2 SSDs, correct? But yes if the SSD is PCIE spec then of course the speed will be less when used on PCIE

m24 slot For example, inserting a PCIe card on a PCIe slot will give you PCIe performance NVMe SSDs connect to the motherboard using