If after making sure that your startup session file is in fact new from boot, and you still have the same issue, I would be thinking of a clean install after a HD format. I know its seems a little daunting at first but it's not really that difficult. The link Peter gave you will also walk you through the process, and off course we are all here should you need help.
The other thing I would say at this point is that I would also be thinking of going inside the D8B and making sure all your cable ribbon connections are seated firmly. I'd check every one of them. All the best.
Andy
Knowledge is the beginning of Wisdom... Let the learning begin.