Strange Read speed on Sandisk Extreme 240gb MacBook Pro 17 inch early 2011

Just installed my new SSD into my 17 inch MacBook Pro early 2011.  I used a benchmarking program called NovaBench and BlackMagic Disc Speed test and both give very strange outcomes.  I get a read speed of just 250mb/s while the writes are brilliant at 495mb/s. (approximately).  I’m using the sata 3 connection and have updated to the latest firmware!  Please help if you can!

try using a different benchmark it may be using uncompressable data. try xbench and see what that reports. 

How did you get on with this? I tried the latest BlackMagic test and it reports read of 500MB/s and writes of 271MB/s which is in line with what I would expect since BlackMagic now uses incomrpessible data for testing.