Reducing write speed in NERO

Hi Guys
I am trying to burn Ritek 8x DVD+R on Sony DRX 720UL using NERO 6.
The problem is Nero (and DVD Shrink) shows me write speed options of only 6x , 8x and Maximum. I want to burning at 4x because even at 6x I dont get good quality video. Before this i was using Taido Yuden 8x DVD+R and at that time it used to give me the option of burning at 4x. Why with Ritek is this option not given.

Is there a way to force the software or writer to burn at 4x ?

You need to have a blank disc in the drive at the time you are checking speeds. Nero does not offer “maximum” unless the drive is empty.

There’s also no way to change the speeds offered, as this is set by the drive, not by Nero.