Found this forum via google searching for NEC-3520 burning issues. Anyway, I just got my burner from newegg a couple days ago. It installed with no problems. But it won't burn a DVD higher than 4X (i only have HP 8x DVD-Rs at the moment).
Recordnow Max showed 14 min to record to blank dvd, and Nero 6 reports the drive's Max speed at 4x (under Recorder/Choose Recorder info).
Some things I did to try to get it to work (thru suggestions on this forum)
Install liggy and dee's firmware update to 1.24. The flash worked great, but it still won't record faster than 4X.
Check DMA mode in Device Mgr/BIOS - both were set to Ultra mode DMA2.
Still won't burn faster than 4X.
ASPI drivers - downloaded and installed latest ASPI drivers. Still no help.
I'm out of ideas. Please help. I appreciate it.