Vasu,
I too had this very same issue after countless hours failed attempts to rectify this!
I decide to wipe the drive and start fresh.
set up was RED Static, RED, And Orange.
Bingo!! This time after a fresh install it was run fast and smooth.
Why can't Tell you, But I did set up and run some test on other boxes to see.
I looks as though on an istall this could happen intermittently.
Hope it helps