Can you make a custom desktop in these websites?

[Cheesenubs]

Hey guys im wondering if anyone can show me good parts for a custom gaming desktop.My budget is $700 ( getting a monitor and keyboard elsewhere). here are the websites http://www.computeralliance.com.au/systems

 

[learningbitbybit]

Configuration Price: $736

Core Components

CPUs: Intel S1150 Core i3 4160 3.60Ghz Dual Core CPU
Motherboards: Gigabyte S1150 MicroATX GA-H81M-DS2 Motherboard
Desktop Memory: DDR3 8GB (2x4G) G.Skill 1600MHz PC12800 Ripjaws RAM Kit PN F3-12800CL9D-8GBRL
Hard Drives (3.5"): 1TB WD 3.5" 7200rpm SATA 6Gb/s Caviar Blue HDD PN WD10EZEX
Video Cards: NVIDIA GTX750Ti 2GB MSI Twin FROZR PCIe Video Card PN N750TI-TF-2GD5OC
Cases: CoolerMaster MicroATX RC-343 Elite Case Black (No PSU)
Power Supplies: 500 Watt Cougar SL500 Power Supply

 

[Cheesenubs]

thanks!