Hi everyone
sorry for my english it’s not my fist language
I have bought a sandisk SDSSDHP 256 GB for my laptop but the read speed is approximely at 250mo/s (I think is normal because it’s sata 2) but the write speed is 80 mo/s very slow 
and I have find no solution about this probleme.
My computer is a asus x200ma us01t I have intall the last bios update and the bios is set to AHCI
For my sandisk the firmwire is x2316RL(I think is the last firmwire)
