Windows 10: dual ( 7 / 10 ) boot question

extra performance from RAID is free.

would cost the same to run 2 X 250 gb versus 1 X 500 gb because raid is a function of the X299 chipset that Skylake-X CPUs use and motherboard has slots for 3 X M.2 SSDs.

in a test such raid is faster than a single drive:

Triple M.2 Samsung 950 Pro Z170 PCIe NVMe RAID Tested - Why So Snappy? | PC Perspective

this test was on an older Intel chipset but it's hard to imagine that a brand new one would work worse.

they said going from single to dual drive is where most performance gain is, but there is still a small gain in performance going from dual to triple. i'd be fine with either dual or triple but it has to be the right size - dual would be 500 GB and triple 750 GB so i need to know how much space i need.

they said the only downside is when you use extra M.2 slots you lose some SATA ports and i verified with the manual for AsRock X299 Taichi motherboard this is the case - i will lose a lot of SATA ports - but i only need one anyway - i don't need all 10 SATA ports or whatever number it has - makes no difference to me.

i'm not concerned with boot time - just want the system to feel snappy once it's loaded.

maybe i should go with dual 500 GB drives this way if the RAID fails i can use them separately, whereas 250 GB drives would be useless separately - too small unless combined in an array. i have a lot of old SSD drives that are all useless because the capacity is too small - this is probably biggest downside to going with multiple 250 GB drives is that they can ONLY be useful in a raid whereas a 500 GB drive i could for example move to my old laptop some day to replace the 250 GB M.2 drive there ... then again, you can't really invest into computer hardware unless it's a case or power supply ...