I currently don’t have DaVinci installed, but I’m pretty sure it will show 01:00:00:00 until you have imported clips into the timeline, no matter what the default is set to. After that it will show correctly.
If you ordered the computer with 16gigs of ram, i would think they made sure you had a 64bit operating system. If the operating system is 32bit, it can only effectively use around 4 gigs of ram. 64bits have virtually no limit.
I’m currently looking around in my own country for what i would have to pay for a new model, but I’ll most likely send you an e-mail within a week to discuss price and such. Norway ain’t cheap!