Hi peeps.
(1) I have a DVD that was burned at 4X on Plextor PX-712A. I did a Q-check PI/PO test using PX-712A as reader and max PIE was 64 with 0 PIF's. The disc reads fine in the PX-712A, but when I put it in my BenQ DW1620, the light just blinks, as if it cant determine what kinda disc it is. After about a minute the light stays on solid and Windows XP just sees it as a blank CD. In PlexTools checking in the DW1620 it recognises the disc as DVD-R with correct volume ID etc, but NO sessions listed. There is 1 session listed if i put it in PX-712A. The media in question is the "DataWrite Classic Grey Top 8X DVD-R" with FUJIFILM03 dye. I thought the BenQ is not compatible with this particular disc, but it cant be that as I have another disc thats the same media type, burnt at 8X on PX-712A, with 400+ PIE's, and 4 PIF's as detected by plextools using PX-712A as reader. This disc is seen by the BenQ no problems! What is wrong? Im thinking i have faulty drive(s)?

(2) Another problem I have is one of the 2 BenQ drives perform really slow when doing a disc quality test using nero cd speed. it often reads at something like 0.08x. My other drive is ok, reades at 8x roughly reading the same disc. CD speed Software is set to read at max speed, DMA enabled.

(3) Yet another problem I have is where the BenQ has burnt a disc at 8x (same media as above), used CD-Speed to check disc quality using Benq as reader - very low PIE's with no PIF's, files read back ok. However, if I then put this disc into the PX-712A, it cant read it! I can hear the drive spin up and down lots of times, but thats all it does. Can these drives read each others discs sometimes or what? Really weird problems these.

Any help would be appreciated. thanks in advance.

Where did you put your 712a and 1620a? What software did you use to burn the disks?
I have both of them in the same IDE channel and they work fine. 1620 in Secondary Master (pin set to master) and 712a in Secondary Slave (pin set to slave).

Regarding point-2:

What firmware versions are your two 1620 BenQ drives running? Hopefully it's B7P9 (retail drive) or G7P9 (OEM drive) or possibly an even later version B7S9. If not one of the above, then you should update it.

Make sure you're running the latest version of CDSpeed. Older versions scan slowly and don't provide any PIF readings. Get the latest version 3.55 here:

http://www.cdspeed2000.com/files/NeroCDSpeed_355.zip

zevia:
PX-712A is on IDE Primary MASTER - Pin set to MASTER
DW1620 is on IDE Secondary MASTER - Pin set to MASTER

Spartane:
I didnt mention that both my BenQ's were DW1600, firmware flashed to retail DW1620. Firmware version on both is B7P9 (RPC1 patched version by the dangerous brothers).

I am using Nero Reloaded version 6.6.0.3, and have just checked that v3.55 of CD speed comes with this.

Jlamy, some people reports compatibility problem with nero 6.6.0.3 although I found mine was fine. Is there any hdd connected to slave in both Primary and Secondary channel?

I'm wondering if your Nero Reloaded somehow made the problems, so lets try with another software. Can you burn a blank dvd with Nero CD Speed "create data disk" (or press F9 key) in 712a and run the "Disk Quality Test" (under Extra Menu) in 1620.

Hi. No hard disks connected to any IDE port as both my HD's are SATA. So the optical drives each have a IDE port all to itself. Yeah I am using Nero 6.6.0.3 at present. I havent any other CD recording software at present. I shall try your suggestion of burning a blank dvd with test data using CD speeed, and will report back.

**update**

I have just made a data disc (F9 key) using CD Speed v3.55 in the PX712A, burned at 8X speed. Media used was DataWrite Classic Grey Top 8X DVD-R, with FUJIFILM03 dye. After the recording had finished I took the disc out and put it into the DW1620 - it reads this disc OK, then used CD Speed to do a disc quality check on it. The results were very good I think. Disc Quality score of 98, max PIE peak of 24, max PIF peak of 4 (not sure if thats bad or not), no POF's. However, I then put the data disc back into the PX712A, then used PlexTools v2.18 to do a Q-check PI/PO scan on it, and the results were quite bad. PIE peak of 1562, 5014 POF's, and the test terminted with error message of "Medium code error (030284)" at around the 4.2GB mark.

I have attached screenshots of the tests so you can have a look for yourself, and correct me if i am wrong.

Which drive is the more correct reader in terms of error detection? Why do the results differ so much from each drive? Does this mean I have one of those plex drives that are lousy readers as mentioned in other posts?

Well the Benq scan seems to be very good . It's kinda funny that u can't read the media with the same drive u burned but u can't with others. Try copying all the data on HDD from Plex. If it doesn't work try it on another PC. If it still doesn't work .... rma