Very nice, although that is a SATA3 motherboard (6GB/s) and that Seagate internal drive is SATA2 (3GB/s). I don't think that works, I might be wrong however.
Here's something you should know about RAM:
Windows 7 32bit Maximum - 4GB
Windows XP Maximum - 2GB
Windows 7 64bit - 16GB
So if you're going to buy 8GB of RAM, make sure you're running Win7 64bit!
As for the Power Supply Unit (PSU);
If money's no object, I suggest you buy a good GeForce card, or a 6-series Radeon