NEC ND-3500AG in USB2 - nero cd-dvd speed problem

[kyleduncan]

Hi,

i'm using a NEC ND-3500AG drive in USB2 enclosure running TDB 2.18 firmware with RPC1 and rip lock. i see that some people on here using nero's cd-dvd speed to test read function of SL DVD-ROMs have a Type of read as CAV. mine reports as P-CAV, and at the end of every disc (whether ROm or DVD-video or DVD-R) at about 15x... it suddenly falls at the end, sometimes dramatically and several times, or sometimes just momentarily. i have anti virus and anti spyware software disabled. any ideas if this is a problem or just normal? (other people scans seem to just keep increasing steadily until the very end at 16x)... for example, a DVD-Video disc burnt using recordnow max 4.5 (burnt onto 8x ridisc DVD-R - TTG02) fell down from 14x to about 7, jumping all over the place... i can attach the nero cd-dvd speed result if i knew how :oS... CDs also dont read totally smoothly...

[kyleduncan]

Here is my output file from nero cd-dvd speed.

Nero CD Speed Test results

General Information

Operating System Windows XP
Drive NEC DVDRW ND-3500AG
Firmware Version 2.18
Serial Number 4Y9EK71S112
Disc DVD-R
Capacity 4.36 GB

Transfer Rate

Start 6.53x
End 7.98x
Average 10.48x
Type P-CAV

thanks again if anyone can help, i think it just might be speed limit of usb2 enclosure?

[wenson]

yes ,I use mCC 004, the speed is up to 12-14X then keep plateau, It may be the uSB 2.o limitation

[cnlson]

mine has problems at 13 x alsoi belive it is a limitation of usb 2. what is your burst rate? need over 24mb to do 16 x

[kyleduncan]

ah i got 19MB and 21MB on differnet occasions. so thats why. well its a relief. however with burnt DVD-Rs the problem is much worse at the end (like in the image i uploaded). but with SL DVD-ROM pressed discs it gets right up to 15 and a bit then just dips VERY SLIGHTLY at the end before finishing... im wondering whether my dvd-rs are full of errors. i cant use k probe to get a reading of them, says my drive isnt suitable..