NEC ND-6650 problem help pls

I just bought this slim drive for my laptop. It is running. I insert a DVD-R which is stated 8x, check dvdinfopro and it only says max 6x. I know this DVD-R is 8x because my desktop have a NEC 2500 which shows 8X. So what is the problem with ND6650? Do I need to upgrade the firmware or something?> Firmware hack or anything??? Please advice! Thanks!

Edit: I just burn a DVD with 8X(another DVD-R). It takes 18 min to burn 4.2GB!!! Why is that so slow?? I usually only get around 10min to burn at 8x on my desktop!

You should upgrade the latest firmware for your 6650.