Need help with Autostrategy on a PX-755

vbimport

#1

I just got a PX-755A , FW upd. to 1.02. I at first used the Drive with default settings, Autostrategy set to “Auto Selection” and PoweRec on. I am using MCC 004 (Verbatim 16x DVD+R). I was burning at 16x when a lot of odd things happened. The drive took forever to get going (I guess autostrategy created the profile during that time). It stopped a few times briefly enroute, to change write speed (I suppose that PoweRec kicked in) and ended the burn on a reduced speed, 8x or 12x, I don’t recall.

What I don’t understand is this: The MCC 004 is recommended media. It’s data should be in the firmware. Why does it create a profile on “auto selection”? According to the Plextools, it should only create a new strategy, if “no suitable strategy is found”.

If I do disable auto strategy completely, which strategy will be used? And how can I keep autostrategy on, but not use it for the MCC 004? Just deselect the mcc 004 strategy active check mark?

Thanks for help or a link, where this is explained.
greetings
ux-3


#2

This is normal behaviour when a 16x strategy is created. The initial test may take up to 2 Minutes. The stopping en route is some mid way re-calibration. If no problems arise burning should continue normally following the (P-)CAV/CLV curve selected as burn speed.

Yes. But that does not mean it’ll get used. The 755/760 series work like this:

[ul]If the build in strategy for recommended media is deemed unsuitable, a parameterised strategy is created for them as well.
[/ul]

So if AS is OFF either a built in strategy is used or a base strategy. Using a plain base strategy is IMHO not a good idea. As for the built in strategies it’s my experience that they beat AS-created ones in the case of Taiyo Yuden but not in the case of Verbatim.

Because AUTO means the drive always checks the media inserted and then AUTOMATICALLY decides whether a firmware-built-in Strategy or a formerly created AS-Strategy fits this media or whether AS will create an altogether new strategy. This is valid for recommended and non-recommended media.

Media quality varies from batch to batch. Quality may vary so much that the built in strategy is not suitable anymore. This is why AS is a good thing! If the firmware-built-in strategy would not match such a variation AS detects this and creates a new strategy instead of applying the built in one.

For recommended media the built in strategy.
For non-recommended media the base strategy.

You can’t. Simply turn it OFF.

No. That just means the drive will ignore that strategy that has been created and stored in the drives nonvolative memory by AS (and eventually create another one).


#3

Well, thanks a lot for that very informative reply. I have hence used the drive without either AS or PR, and I got a rather fast burn, which went up to 16x near the end. A PI/PO check maxed at about 40 near the 1 GB region, then went down again to about 10-15 for the rest of the disk. Hmm… Is it worth having AS and PR on, I wonder? From what you write, I should try AS on and PR off.

Greetings,
Ux-3


#4

As a sidenote: My 716A did not create these strategies when on AS. The window, in which the strategies are listed, simply remained empty. The results were worse than on the 712A. Does that make sense?

Greetings
ux-3


#5

Yes, the PX-712 is a better writer than the PX-716 (if you don’t need DL), and the PX-716 never uses AS for media for which it has a built-in strategy.


#6

Contrary to the 755/760 AS in the 716 cannot ‘override’ the built in strategies in the firmware. AS only gets applied if the media is totally unknown to the firmware. The 716 is a very good burner up to 12x. But for 16x it needs absolutely high quality discs to achieve good results at full 16x speed. Even good quality brand discs like Verbatim or Yuden will be slowed if the slightest problem arises.


#7

Thanks a lot for that information, Alexnoe! I am tempted to put the PX-712 along with my PX-755, for single layer burns. (I will put up another thread for my other potential use) If I recall correctly, an MCC 004 gets done quicker in the 712 than in the 755. Since the 712 does near perfect burns, I wonder if I can cut even more time by disabeling PoweRec? I shall try this eventually.

Greetings
ux-3

Edit: Thanks to HWP as well, didn’t see it, when I posted this!
I found that the 716 will do decent burns up to 16x on Verbatim, IF you deny it the chance of having second thoughts about it (PR off). On the discs I have done it is the 1 GB region, which has the most pie. Probably the media (MCC 004)


#8

I get this result on MCC-004 with a PX-712: http://www.alexander-noe.com/cdvd/px/sample_pictures/Mitsubishi_16_+R/#plextorpx712_120

Sometimes it slows down to 10x, sometimes not.


#9

Affirmative. Mcc 004 used to stay under 10 for the whole run. (newer spindle peaks at 20 @ 1 GB) I have not yet noted a slowdown at 12x, but I don’t usually sit in front and watch, so it could have happened during regular duty. Never during observed tests however.


#10

I would like to know if my problem is the same problem ?
drive uses UDMA 2 AS is on autoselect ) powerec is on it seems to lock the speed on 6 x
is it save to turn of powerec AS has a strategy in the db of 6x but everytime i take a disk from the spindle it still takes 1 minute before the actual burn.
related post:
http://club.cdfreaks.com/showpost.php?p=1434774&postcount=97