Flashing back to B7T9 after using B7U9



After getting a couple of very bad 16x TY02 burns using B7U9 I decided to go back to B7T9. I was quite apprehensive because I had never gone back in firmware with the BenQ before and I keep reading about people flashing back to B7L9 before flashing the firmware they really wanted to use. But I decide to be brave and just flash it straight to B7T9 using the official flasher, followed by a restart. And the result was a good 16x TY02 burn and very similar to my other B7T9 burns of this media. Is this B7L9 flash really required before flashing B7T9 or has BenQ sorted whatever caused it to be required in the past?

Maybe someone could also fill me in on what prompted this dual flash in the past. Might be something that I should add to the FAQ…


The B7L9 method was necessary for me…to get the same burn quality when going back from U9 to T9…but if you are getting the same quality dont bother…
I do recommend rebooting twice after flashing…seems on my system a must…some have even suggested turning off the computer completely

I did not do a L9 flash then burn then flash to U9 to see if this improved my U9 performance…U9 kept knocking my TY02 to 12x in the middle of 16x burn


I think a lot of people thought flashing back to B7L9 had the same effect as clearing the EEPROM in Liteon drives. I’ve never noticed any difference in doing this IMO.


well it seems to help my drive or system to allow a clean flash…when I flashed to U9 I did it over T9…then I flashed over U9 to P9 and my burns sucked…so I did the L9 flash and burn a disc and reflashed to T9…I also saw a post from Benq tech to reboot twice…so I always do this between flashes

It maybe a placebo but on my system it seems to help get a clean flash to P9/T9


Yes, I was wondering about that. Perhaps in B7L9 there was a significant change (from previous firmware) that required any (for lack of a word) “learned” data to be flushed.

It’s interesting that the only time I’ve had a problem with this BenQ drive is after a flash. When I flashed to B7T9, I ended up with a lead-out lockup that only went away after the drive was powered off. When I flashed to B7U9 the first disc I burned would not eject until after a restart and in this case I had even powered off the drive after flashing it. Nothing else strange has happened after a power off and a couple of restarts :confused:.


This sounds very strange… :confused:
Could this behaviour be chipset specific? (I’m on $ntel 865PE.)

  • I have flashed forth and back to B7T9 <–> B7U9 many times. Two times this evening without an issue.
  • After a flash on my BenQ 1620 I don’t even bother to restart. :wink:

BTW, tried the B7L9 once a while ago when flashing back to "earlier "firmware, but didn’t experience any improvement or decreasing in burn quality.


I’m also one of those who don’t even bother to restart after a flash.

The only difference I noticed regarding rebooting and turning off is… I somehow believe a “just turned on” cold drive writes a little bit better than a “3 hours running” hot drive. :slight_smile:
My best records usually came at the first burn of the day. But I think, even if it is ture, the difference is really small and it is more of a heat issue rather than EEPROM issue.

On the other hand… it looks like my TY T02 quality is getting better as time goes on. I mixed the order of discs in the spindle just after my purchase so it is hard to believe that I picked up bad ones first just by chance. Is it really ture that there is no “learning mechanism” in the 1620 drive?


to me no difference…BenQ ppl also wonder why this was tot to be??..:bigsmile:


Not sure I understand this comment

I have tried to flash and burn and back n forth so t ospeak…but on my system…this just does not make a good burn…not sure why

My system is overclocked and Prime95 stable…memory tested with memtest86…so who knows…I hate the hassles of L9 sequence but it does make a difference for me, at least…so I do it…I would prefer not to waste the time

I have also found…safe mode does not help or hurt…


On my system the transferrate is reduced from 23 MB/sec to 13 MB/sec after each flash, even to the same firmware. Device manager still displays UMDA2. This problem is solved by either rebooting or disabling/enabling the IDE channel the drive is connected to. Maybe your system also disables the UDMA mode and causes the problems you see.


if it does disable udma2…it does not show that in device manager


Maybe…I’m using an nForce 2 mobo.


ala42 told me that it still displayed udma2 in device manager but if you check the transfer rate, it was only getting to 13MB.


From experience, the BenQ (and Philips) flasher leaves the IDE channel busy cos the IDE LED is always lit till a system reboot.


I’ve crossflashed and reflashed tens of times without ever using the B7L9 method. I do, however, always restart 1x after flashing. I’ve also never had a “bad flash” as far as I can tell.


nealh i am saying that to me flashing to L9 and another firmware or direct flashing straight to the other firmware makes no diff to me…

and also RD guys have said that there is no such “cleansing” going on with the L9…


Ok…I have no idea why I can not simply flash from one firmware to another without L9 first…

I know when I went from G7C9 to B7P9…I used the flash to 1600 then to 1620…and everything was ok…
First time I went to T9…I got poorer burns so I flashed back to P9 via L9…then I placed this drive in an enclosure and flashed to 4NL9

when I got my second burner flashed to P9 via L9…then straight to T9…not so good so I tried L9 much better…

From T9 I tried U9 straight out but was not happy so Flashed back to P9…got some ugly burns …so used L9 and went to T9

I always use Benq flasher except when I went from G to B FW used winflash (no 1600 flash)…G–>B

I believe that L9 does nothing if the RD say so…

I have no idea why my burners…system are finicky…I just know I seem to need to go backwards then forward… :confused:

I may try U9 again with L9 and see if I am dreaming and have convinced myself of some placebo affect


Its all BS. Cleansing? If this was true would it be a known fact told by benq tech employees?


gng thru L9 for me is also no effect.

i flashed back to B7T9 from B7U9. somehow i hav not been getting good results from B7U9, and the burning speeds get reduced


heheh, read this carefully crafted Singlish post again, the official stand is hidden somewhere in that line. lol