I'm a bit confused about something, when SSD reviews are measure performance at say a QD of 32 in iometer where are they setting QD in the interface ?. Are they doing this by creating 32 Works or are they using the # of Outstanding I/Os ? I think of QD in the sense of it's classic definition "Queue depth, in storage, is the number of pending input/output (I/O) requests for a volume" So it has to be mesured. I did a simple test using I/O meter I using a 1 gig test file with 8KB 100% sequential read. using 50 outstanding I/O -on SATA 7K drive the Perfmon queue length /sec measured 49. ok that's a one to one correlation. -on a SSD Preval Elite the Perfmon Queue length / sec measured 48.3 -on RAMDrive the Perfmon Queue length / sec measure .3 It does not mater to what value I increase the Outstanding I/O value, 100, 500, 5000, 50000, 500000 the Queue length / sec always stays at around the .3 with a ramdrive. I tried two different product same result. I would have expected to eventual start seeing latency increate as QD does ? Can anyone explain what's going on here ? ( Is it that ram latency is so low that the Perfmon Queue lenght/sec is not showing me the difference of latency that might seem big when viewed at the nanosecond scale ? ) (cpu on test system is Xeon x5560 with DDR3 PC12800 ram) Naim.