I am planning to build my own PC, I am new at it so im doing research first and taking it slow. However, I am experimenting on my old Dell Dimension 4600. It only has 512 mb of ram right now, looking to max it out for fun. I was looking on newegg.com and trying to decide what memory to purchase. In the Dell Manual it said something about "non ecc" what does that mean? also any recomendations for filling the 4 slots with 1G each i like the kingston brand stuff, it sounds pretty reliable. 2700 (333) or 3200 (400) 184 pin. Also I wanted to add a second hard drive for pictures and videos etc. I have a seagate 160gig ultra ata that I got from a brand new DVR. Do you think it will be compatible?