DVD Burner speed issue

[Marin85]

Hi again ,
that´s not a topic about my Z61p upgrade, but about a weird issue with my ultrabay DVD Burner. A few weeks ago I installed Vista Ultimate x64 EN-US on a newly obtained Hitachi 7K200. After installing Nero 8 I noted that it would burn DVD+- R with max 4x and there is no way to change this. I tried ImgBurn but it would also burn DVD+-R with max 4x. The point is that I could burn DVD+-Rs with up to 8x with my previous Vista Business x86 DE. What is more, Everest still reports writing speeds up to 8x for DVD+-R... Any insights are appreciated!

Marin