PCIe layout is easy to discuss – you get a lot of PCIe. Due to the extra length of this XL-ATX board over the standard ATX, there is room for seven PCIe slots. If they are Populated with GPUs, the order becomes:
One GPU: x16/x1/-/x1/-/x1/-
Two GPUs: x16/x1/-/x1/x16/x1/-
Three GPUs: x16/x1/x8/x1/x8/x1/-
Four GPUs: x16/x1/x8/x1/x8/x1/x8
The four slots designated as GPU slots are PCIe Gen3 compatible, whereas the other three slots are PCIe Gen2 x1 slots. I assume that as the x1 are full length slots MSI has had feedback that suggests these are beneficial to those that use them. However, a board like this is unsuitable for GPU folders or simulators wanting to use more than four GPUs as the x1 limitation is quite severe (ideally, the x1 slots would have been multiplexed to x4/x4 with the x8 slots when occupied).
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