Samsung 950 pro 256mb m2 ssd specifications usage application client pcs capacity 256gb dimensions lxwxh max 8015 x max 2215 x max238 mm interface pcie 30 x4 up to 32gbs nvme 11 form factor m22280acirceuro controller samsung ubx controller nand flash memory samsung v nand dram cache memory 512mb lpddr3 performance sequential read up to 2 200 mbs sequential write up to 900 mbs 4kb random read q