Transfer Rate speed standards? -- Is 16x too fast for testing?

vbimport

#1

When running the Transfer rate test on some rescent discs, I’ve gotten perfect results when I run the test on my BenQ 1620 (which max’s out at approx. 7x ), but when I run the test on my Liteon 167T DVD-ROM (firmware 9S16) I get some spikes towards the end.(between 14x & 16x) The same disc(s), have a perfect transfer rate test when I test using my Plextor 716A.(speed max’s out at 12x)

So if a disc "spits’ & “sputters” toward the end of a transfer rate test on a DVD-ROM drive between speeds 14x & 16x, would you say it’s a bad disc? But yet the disc runs (transfer test) perfectly at lower speeds (like at 7x on BenQ & 12x on Plextor), is it ok? What’s considered the max speed for transfer rate testing? Is 16x too fast for testing?

BTW, some of the discs that had spikes between 14x & 16x on the DVD-ROM drive, had excellent CD-DVD Speed scans and the discs were also tested in Kprobe. (scored 99 in CD-DVD Speed) (Kprobe PIF=2 PIE=6)

Attached are two scans showing the problem areas. But again, these discs test thru Transfer rate perfectly on every other drive in my system. These drives are slower tho.


#2

Apply speed patch on your BenQ and see what happens


#3

Ok… I will find it and see how that does.

So any burned DVD SHOULD be able to show a perfect arc even at 16x on a DVD-ROM drive? I’m mainly a +R user, but the TYG02 -R media I have never has a problem… even at 16x. The TY02 I have (Fuji, RIMA, & Printable) DOES spike between 14x & 16x inconsistantly. But sometimes the test is perfect. The TY02 does it no matter which burner I use.(716A, or BenQ 1620)

Attached is scan of a TYG02 -R disc:



#4

Some drives simply do not read well above 13x-14x, and it does not always mean a “bad” disc. Also, once a drive has been triggered to slow down, the read speed can drop a lot, and never recover. So, sometimes, reading at 12x is faster than 16x. (quicker). Transfer rate tests are just one more tool, and by themselves they do not establish a “good” or “bad” disc.


#5

Thanks for your help [i]rdgrimes[/i]. Basically I’d like to scan at the faster speeds because the test won’t take as long. But if I get a few spikes… say between 14x & 16x, I’m wondering if I could then test it in a slower drive to see if any problems show up. And if the test runs perfect, consider the disc ok.(Tho I know that’s just a guide) Because if there were problems, wouldn’t they show up in the BenQ at 7x?

BTW, any of you use Transfer Rate test as a guide for the majority of your discs? I thought I could cut back on time if I use Transfer rate for the majority of my discs, and use PIF/PIO testing for backups and “important” discs, just as a secondary precaution.


#6

Transfer rate tests are just one more tool, and by themselves they do not establish a “good” or “bad” disc.

Most people feel that 16x is the best speed, because it will separate the best discs from the lesser ones. But it’s only relevant for THAT drive. If your drive reads some discs well at 16x, but not others, then it’s telling you something. If it reads most discs well at 16x, then it’s telling you nothing. If it reads very few discs well at 16x, then it’s telling you nothing. It’s all drive-specific. 7x reading tells you even less, but the same things are also true at any speed.


#7

Makes sense. But would it be reasonable to say that the TYG02 -R media (with my burner) is better than the +R media, since every single disc worked perfectly at 16x, while a few of the TY02 discs had severe spikes? Well… actually I guess it only tells me that my TYG02 burns from that burner get along better with THAT drive than the TY02 burns do. Sheesh… this gets complicated.:eek::bigsmile:

EDIT:
Attached are scans of the same disc scanned with the BenQ.(after speedpatch) And 2nd scan is same disc scanned with Liteon 167T.




#8

Somehow i knew the BenQ would have no problems @ 16x :smiley:


#9

Yeah… the 1620 has seemed to be a great reader. Discs that have been scratched up bad enough that my 167T wouldn’t read them, would read fine in the BenQ. Thanks so much for letting me know about the speedpatch.:iagree: I guess I’ll find out, but how does the 1620 do (speed wise) with DVD9?

BTW, my trusty ol’ 167T has earned it’s keep tho. Haven’t had many discs it wouldn’t rip.


#10

Put a pressed DL in and run the transfer test. It won’t take long :wink:


#11

The 166/167 drives are well known for slowing down at the drop of a hat, and they never recover after that. Many burners do the same thing. You can find as much variation between drives of the same model line as you do with drives of different models. But, in general, the drive’s error correction scheme is responsible for this. Very small differences in hardware and firmware can affect this a lot.