This chipset has been extremely solid and seems to be quite good at supporting 1600 DDR3 memory.
Phenom II X2 550
For $100 it gives you quite a bang for your buck. Unlocked means easier overclock for a beginner like yourself.
G-Skill 1.5v 9-9-9-24
Samsung 500GB/Platter F3 Series - important for speed/heat/power usage
in-win case with 300 watt dual rail
Granted, there isn't a lot of room left on the rails but the power supply is great quality, solid consistent voltage. About the only thing that seems to vary much is the efficiency. At normal load movie watching/gaming etc The power supplies tend to be 75-85% efficient. In-Win's website shows they have two 300Watt PS's one 80% rated the other not, the specs the same. My guess is that they simply test them out the door and anything better than 80 gets the higher sticker price and 80 logo.
The board is a no brainer. Gigabyte is second to none in my book. I know many here will poopoo uATX at all, but it's a good compromise for those who want a powerful machine without feeling like they have a full server in their room.
The Phenom II 550 runs a 80watt TDP, 3.1Ghz and overclocks like crazy. Quad Core Athlon 602 is about the same price but is only 2.6Ghz and suffers at gaming.
For memory, I choose G-Skill, this model in particular because it's rated at 1.5volts and runs far cooler than other OCZ and corsair that I've tried early on.
The hard drive is again a no brainer. You want the latest 500GB/Platter technology for sure. Faster speeds, better EE. Samsung does it right. Seagate is my second choice. Avoid WD in my view. With even just a single drive. I can peg my 1000Base-T network at home (yes 110MB/sec) sustained for 160GB worth of video between computers.
The ATI 4770 is the mid range card based on the new more EE process. It's sort of the new age 4830 in terms of low cost good performance but consuming a full 15 watts less idle and 30 watts less on full load.
The case I choose is really about the size and features. Just barely enough room to get some PCI-E cards in there. The cooling design on the case is impressive and it's small size is used to it's advantage. The Video card for example acts as a wall between video card heat and the rest of the system. It's also got a isolated CPU compartment to intake cool heat and isolate it around the CPU. It's also got tool less design, smooth edges etc. Very easy to work with. The power supply is also down by the PCI-E slots.
I wrote this quick so excuse the errors. I can't sleep tonight and needed something to do. Frankly I can't find a better system to build or recommend for people.
It runs well under 100watt idle and 170 or so at load without overclocking using my kill-a-watt. It also stays crazy cold.
If you want Quad Core without uping your power supply use the 905e (2.5Ghz) or this guy:
while the board supports 125 and 140 and this config has worked in a test, I wouldn't recommend pushing the PS that hard.
J&W MINIX (ITX 780g) Athlon X2 5050e
DFI LanParty JR (uATX 790gx) Athlon X4 620
DFI LanParty JR (uATX 790gx) Phenom II 940