Over the past few days, I have an ongoing problem with portions of my iPad screen going black. For example, when i pull up the onscreen keyboard, a few of the keys on the edges can be seen, but the rest are black. The touchscreen still actually works (I think) for typing, as i can touch where the keyboard should be and letters will appear in the document or email i am trying to type. Other times, a quarter or half of the screen will be back when viewing a webpage in safari, and that part of the page will 'travel' when i scroll through the page. This started about the time i tried to do a synch on a new computer this past weekend. Any suggestions would be appreciated.