it is a iphone 3gs and i dont know the firmware i bought it and i payed someone to jailbrake it for me and i dont know the exact firmware. where can i get the just boot thing cause i have downloaded some stuff that has it on the extras but it does not work. i have two computers i am trying it on and one stopps in the middle of one and my other goes throught the whole process but it just goes to a black screen.

hey so my iphone is a tethered jailbrake and it died and i am trying to boot it but it is not working is their any pointers or anything i might be doing wrong?? it is an older os like 4.2.1 or 4.3.5 or something i am not sure. i have not had my phone working for a few days and am hoping to get it working again soon. i would switch to another phone but my family is borrowing all my other phones and want my iphone working sence i payed so much for it. Thanks