re :

j'ai trouvé ça sur un forum :
pour l'option du new bios toxic a propo du patch pour la lecture des dvd dl:

a priori ,ils disent de lancer le jeu gravé mais avec l'option dl activé et surtout avec le fast boot , a priori il ne faut pas passer par l'explorateur de la ps2 si g bien compri :


DVD+R dual layer media support

Until now it has been impossible to play DVD9 games backed up onto dual
layer media on the PS2 due to a problem with reading from the second layer
because the data format on burnt DL discs is different than on pressed
discs (burnt = OTP, pressed = PTP). However, we have discovered a software
hack which enables the PS2 to read even burnt OTP discs meaning it is now
possible to make backups of dual layer games such as GT4. ToxicBIOS includes
an "auto-patching" mechanism which applies this patch on the fly. The
auto-patcher is disabled by default, to enable set "DVD+R DL Support" in
the settings menu.

NOTE: Unfortunately due to software restrictions the auto-patching will
not work if you boot your DL backup from the updated Sony browser
stored on the HDD. If you are using the updated browser then in
order to play your DL backups you must boot them with fastboot.
If you are not using the browser update then there are no
limitations regarding how you can boot DL backups.

enfin si je ne me trompe pas , si quelqu'un sait lire l'anglais qu'il le traduise pour etre sur que ce que j'avance est correct .

Merci