(adsbygoogle = window.adsbygoogle || []).push({}); Ok I am planning on jailbreaking my ps3 i have the normal slim ps3 i am running on 4.66 i have been told I need to downgrade to 3.55 then use multiMAN V4.66 is that true? If i do this will I be able to play online I heard if you downgrade it to 3.55 you cant play online i know i sound stupid asking that?

You'd need an E3 flasher in order to install a CFW. People call it downgrading, though if you use a patcher, there is no actual downgrading. You just patch your NOR flash & install a custom firmware.
You can no longer play online on 3.55 as there is no longer a spoof available for it, but you would install a 4.xx custom firmware, and use a spoof to get onto PSN, allowing you to play online.

You can buy an E3 flasher online, however I would suggest making sure you have a downgradeable PS3 first, as it would be a waste of money if you don't. There is a serial number on the back of the console on a white label, the model number will begin with 'CECH'. If the number is 'CECH300xx', it's not possible to downgrade at all. (the x's are variables, any serial number beginning with 3 cannot be done.)
If the number is 'CECH25xx', then you have a chance, but you would need to run something called 'MinVerChk' on your PS3 (Google it.)

Not that it needs mentioning, but all super slim models (CECH4xxx) cannot be downgraded full-stop.

Links:
PS3 Slim Downgrade Chart: You must login or register to view this content.
E3 Flasher (UK): You must login or register to view this content.

Hope this helps you out a little.

Which model do you have? There are some SLIM model which cannot be downgraded to

SKU Models -> You must login or register to view this content.

i have the slim not super slim just slim

The easiest way to check is the date code on the bottom of PS3

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Then look at this chart to see if your PS3 can be downgraded

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