I would also suggest getting better PSU, even for the sake of future expansion.
I personally dislike the acoustic characteristics of Maxtor HDD, you should probably get something better, like Seagate.
Also, is there a need for Quad-core? what you will be using this PC for? If for gaming and everyday use I would strongly recommend a faster dual-core, like the E8400/8500. They overclock better and will perform better too in gaming than slower quad core.