I recently had my HP laptop fail and replaced it with a Lenovo Ideapad Y400 with an i7 processor, Nvidia Geoforce 9T video card, and 8 GB or RAM. It's running Windows 8. I mainly use Capture NX2 with Some CS6 for post processing.
I've had a couple of minor issues with reprocessing old files, but in general have had no issues with new D800 files. I will probably upgrade the RAM to 16GB but I don't think its really necessary.
By the way - I would stay away from HP with AMD processors. I've had 5 of 6 HP laptops fail within 18-24 months or purchase over the past 4 years.