I just expirienced this problem 2 weeks ago when I bought 100 TDK 8x DVD+R. Whatever program I use the burn is 2x slower than the optional, if I burn with Nero the Used buffer is at 50%...
When I tried to install the driver it says the it couldn't detect the drive but calls it Sohw-812s US0Q eventhough it is the right driver downloaded from LITE-ON.
I have read something about changing some boot options but I haven't really got it..
The drive also burns files (4.3gb) with problems, often making em skipping chapters
Hope somebody can help me
Thanks in advance