[vmin81]

is the firmware of 8530 is same as 8520 i mean i can update bb 8520 of 8530 firmware or i cant

[cyberdyne]

I wouldn't risk it.
The stickys at the top of this forum have two specific firmwares available, one for the 8520 and one for the 8530. If they were cross-compatible I'm sure there would be just one for both.

[MidnightDraven]

No, you can't.
8520 is for 8520 and 8530 is for 8530.

[NJBlackBerry]

Cyberdyne - as an FYI, you can't put the OS for one model on another, even if they are in the same family. 8300 software won't work on an 8310 or an 8320. It will not load.

[cyberdyne]

Cool, thanks for confirming what I think I was trying to convey, lol ;)