you see, i have a psp at firmware:3.71 m33-4 with a devhook:devhook0.4x launcher for 2.71. i was wandering how to upgrade to 3.90 m33-2 and if i manage to do so , will my iso games still work and do i have to change the dev hook and how. the last time i upgraded my psp to the original firmware i could not play my iso games anymore. it cost me 50$ to get it fixed back to 3.71m33-4firmware, and i think i was ripped off . i hope someone can help me
