I suspect you would lose the two last M.2 slots. If you look carefully at the card in the picture, you can see the right-most M.2 slot traces going to the right most part of the PCIe connector without any switching hardware in between, which would (to me,) indicate that half the lanes would mean half the M.2 slots if all the others are configured the same way but, the contrast and brightness makes it hard to see if the others are wired that way. If ASRock is touting the length of the M.2 slot to the PCIe slot, then I suspect that they're not having lanes cross each other by grabbing two lanes from the beginning of the slot then two near the end of the slot to allow them all to drop to 2 lanes if it's electrically 8 lanes. It would probably cost more to produce as well.Look at it this way, if you're considering using 4xM.2 SSDs, you're probably not using a mainstream platform.

Interesting times in that we are on the cusp of am4 having the same raid ability as TR4 it seems, w/ the new 400 series mobos. These new mobos should be able to do native bootable nvme 2x raid using an 8 lane dgpu.



I like the shorter traces.



I am skeptical of the shroud and cheesy fan arrangements on some of these board. I think I prefer a bare board & make my own ventilation arrangements.



These powerful raid arrays are a case in point imo, as to why lane/core rich and quad channel ram amd tr4 is so much better than a similarly priced intel with its increasingly marginal ipc advantage.



Only a very few expensive intel rigs offer 16, or even 8, lanes spare w/ a 16 lane dgpu installed, so intel buyers can forget it. Do not be fooled by Intel's onboard nvme ports. They have a combined 4 lane bandwidth that just one good nvme could saturate. Using their alleged nvme raid on these ports is ~useless for speed.



Folks dont seem to have got their heads around what a powerful resource ~ram speed storage is/promises to be. I find it hard to believe many apps like games & vid editing can't use it to good effect. On Vega, such arrays can even be used as gpu cache extenders, for effectively unlimited gpu memory size.



For now its expensive, but getting better and cheaper, but speed should not be confused with costly capacity - that's a separate issue for a separate drive. Very fast 256GB Evos are $120US ea., and pretty fast (~60% of Evo read speed & similar write speed) corsair (superior MLC nand) 120GB are $70 on newegg. Even 480GB is huge as virtual memory or a scratch drive.



It bears reiterating that these are mere adapters. They do no processing. They simply make a direct link from the nvme drive controller to the cpu. Just because there are expensive, seemingly similar, intelligent raid cards like highpoint out there for $500+, doesnt mean these simple cards need to be dear too. $85US+ is too much. $55US~ would be fair, but its a sellers market atm.