Read/write (25.4/32.3) extremely slow after cloning.

Hi,

I just purchased two (2) Crucial MX200 SSDs 500GB.

I have carefully followed the procedure to clone the SSD in my MBP. When the first one tested poorly, I cloned the 2d SSD and received the same results. They both initialize and startup but when I test them out on Black Magic they show 25.4 read and 32.3 write.

The old SSD (120GB) was 128-130 Read and 375.4 Write.

Can anyone suggest what my problem might be and how to fix it?

Thanks in advance for your assistance.

Greg Macaulay