I am not asking you to switch to another burning app, but do other apps (Easy CD Creator, NTI, etc.) see the drive's 20x speed properly?
Also, was there a time when Nero saw the 20x speed, or has it never worked properly.
Also, have you updated to the latest version of Nero, which is 22.214.171.124? You can get the update at www.nero.com
, and I would recommend downloading it if you haven't already done so.