If it's set at 4x, it will burn at 4x.
If it's set as 8x or Max, it will likely burn at 8x (or higher depending on your burner).
This is the general rule. However, depending on the variable media quality, windows randomly turning off your dma & which way the wind is blowing in Antartica, it can vary.
First of all .. What is your burner?
If you have nero, can you run the infotool with one of your DVDR's in the drive & post the log between "[ code ]" & "[ /code ]" tags. Delete the serial from the log before posting it. 
This will allow us to ensure there is no conflicting aspi layers / programs / etc without asking twenty different questions.