Lexar quote random 4K performance for the 480GB NM600 as up to 188,000 IOPS. With our standard 4 thread testing we couldn't get close to that figure, the best we saw was 132,115 IOPS at a QD of 32. However, a quick test at QD32 with 8 threads saw the random read performance rise to 150,208 IOPS, still short of the official maximum figure.
4K Random Read v QD Performance Compared
The drive didn't handle our 4K random read test very well at all even at QD's 1 & 2, however it must be said that the performance picked up at a QD of 4 at 83,078 IOPS before dropping back at a QD of 32.