GPU: Gigabyte Nvidia GTX 750ti - $189
CPU: Intel Core i5 4440 - $214
Case: Antec 300 - $82
Mobo: Asrock B85M Pro 4 - $89
PSU: Antec 520W High Current Gamer PSU Modular Extreme - $99
RAM: G Skill 8G(2x4G) DDR3 1600Mhz PC12800 RL 9-9-9-24(CL9D-8GBRL) $99
HDD: WD Black 1TB - $92
Optical: Asus DRW-24D3ST OEM SATA 24X DVD-RW Black - $20
Total = $884
All prices are from: www.umart.com.au
I would consider this a high quality, power efficient, cool running budget rig. You cannot overclock (easily) using this motherboard or CPU, however overclocking your CPU usually necessitates the purchase of an aftermarket CPU cooler ($).
The PSU is of high quality and is frankly overkill when you consider that the video card included can draw all of its power from the PCI-E slot. It's also modular (you'll thank me later). If you want to future-proof more for a beastly upgrade later on then I would recommend a Corsair HX series PSU, a full sized mobo, and a bigger case. This will of course cost you more.