[New System Build] recommendations

Add this to it:

1 G.SKILL 4GB (2 x 2GB) DDR2-1066
1 SAPPHIRE Radeon HD 4670 100255 HDMI Video Card
1 Western Digital Caviar Black 750GB 3.5" SATA 3.0Gb/s Hard Drive
1 Antec Three Hundred Illusion Black Computer Case
Antec earthwatts EA430 430W Continuous Power Power Supply
1 SAMSUNG DVD Burner Black SATA Model SH-S223L LightScribe Support

This may work with an old version of the bios on your choice of motherboard also:

Chinese website Coolaler.com has learned that MSI's newest AMD 785G motherboard, the 785GM-E65, can not only unlock the two disabled cores on the Phenom II X2 550, but also provide reasonable overclocking stability for the processor. Coolaler used a retail Phenom II X2 550 on the new motherboard, and simply set the ACC feature in the BIOS setup to "auto" (which enables it from the BIOS end). The system booted with all physical cores on the processor enabled, and allowed overclocking it to 3.609 GHz (18 x 200 MHz, 1.344 V). The chip was subjected to full-load using two instances of Orthos to test its stability, to which it emerged fairly stable.

http://www.techpowerup.com/100519/ [...] cking.html

Certainly, Gigabyte and Asus are better quality than MSI. They are Tier 1 manufacturers.