QUOTE(chokia @ Jun 3 2011, 05:05 AM)
Is there any huge different between Ultrasnow, Snowbreeze and GreenPoison JB?
my freaking IP4 cant take other than greenpoison.
You are talking about things that are not related to each other
1. Ultrasn0w - allows you to unlock your phone (for those locked set ie. AT&T set etc etc), an unlock can only be apllied once a phone is jailbrken
2. Sn0wbreeze - a Windows program that allows you to create custom firmware which in turns allows you to jailbreak your phone. Custom firmware is a modified iOS firmware that allows you to preserve your baseband (why do you need to preserve baseband? -- well since ultrasn0w can ONLY work with certain baseband so you will want to make sure that during the upgrade, you don't upgrade the baseband)
3. Greenpois0n - A multi OS program that allows you to jailbreak your iPhone but only up to firmware 4.2.1, firmware higher than 4.2.1 is not supported
For firmware higher than 4.2.1, you will need to use redsn0w - WARNING, redsn0w is for those with factory unlocked iphone, those who only require a jailbreak and does not require unlocking of the baseband.
Follow binoobob suggestion and read up the Jailbreak thread.