Exploited consoles is difficult to understand to a person with no research, so my advice would be not to get DEX.
And to jailbreak, its obviously that you need to downgrade to 3.55 first.
You cannot jailbreak on any firmware above 3.55, I'm sorry.
What you'll need to do is to check if your ps3 is compatible and has been on 3.55 or below, and then use a E3 flasher.

Victoria_Moore wrote Exploited consoles is difficult to understand to a person with no research, so my advice would be not to get DEX.
And to jailbreak, its obviously that you need to downgrade to 3.55 first.
You cannot jailbreak on any firmware above 3.55, I'm sorry.
What you'll need to do is to check if your ps3 is compatible and has been on 3.55 or below, and then use a E3 flasher.

^
But you can RTM on cex, with CCAPI.
There are alot of tools for cex, so if you flash it with yout E3 Flasher u can stay on cex, there are alot of tuts out on youtube how to RTM on cex.
But as Victoria_Moore said, you device has to be compatible to jailbreak, because some newer consoles are fabricated with 3.56 so they are not jailbreakable, hope helped you out, if you have any other questions

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