i have the same problem. 1. plug it in with power chord 2. Apple logo pops up for 1 or 2 minutes 3. i start holding down button combinations, and the apple goes away, screen seems like it goes black. but at night you can see the display is fully lit. 4. holding "home and sleep" to get the red slider gets me a horizontal one pixel blue line, a quarter of the way down from the top of the screen. if i plug in to MacBook pro... 5. same as step two above but 6. image capture launches and photo thumbnails appear from my camera roll, while apple logo remains on screen. 7. at that point i have about 30 seconds to copy photos to my desktop, then the phone restarts and image capture loses connection. 8. steps 6 and 7 repeat endlessly. i have replaced the dock connector once, with another known functioning iPhone (we have two in the family). i have also swapped batteries, but i'm having the same behavior... i have a "new" dock connector coming in the mail, so i'll try that next. in the meantime i'll swap logic boards...

NOTE FOR REMOVAL--FINAL PIECE: as i was removing the last part of the complex ribbon assembly and arrived at the final connection to remove, i could not figure out from the photos what was holding it to the phone chassis. i will try to describe it so its more clear, since there doesn't seem to be any description of what i'm talking about...

1. the final attachment is held on vertically to a chassis wall. use a small flat object, perhaps your fingernail between the black foam and the vertical wall. it is a trick to pull the final piece off the wall without damaging the black foam. mine is now damaged and will not likely re-stick.

it may not normally be a problem since your new piece may come with a rubber sticky thing. but in my case, i was removing a good one to replace a damaged one on my other phone.