Okay so i'm not chasing a new computer too soon but i just need some ideas to suggest to my mum on which would be the best way to go. My first option is to buy a computer from scorptec.com.au with the following statistics:

Intel Core i5 3470 (3.20Ghz/6MB/Quad Core)
1 Motherboard
Asus P8Z77-V LX, Intel Z77 Chipset, 4x DDR3, SATA3, USB3.0, 8 CH, HDMI, DVI,
VGA, PCI-E 3.0
1 Memory Kingston 8GB Kit (2x4GB) 1333MHz DDR3, Dual Channel
1 Hard Disk Seagate 2TB Barracuda, SATAIII, 7200rpm, 64MB Cache
1 Case Corsair Carbide 200R Compact ATX Case
1 Optical Drive LG GH24NS90 24x Dual Layer DVD Burner, SATA
1 Video Card
Gigabyte Geforce GTX650 OC Edition (1110Mhz), 1GB GDDR5 (5000Mhz), PCI-E 3.0,
2x DVI, HDMI, VGA
1 Power Supply Thermaltake Litepower 500W Power Supply, PCIE, SATA connectors
1
Anti Virus / Internet
Security
Kaspersky Internet Security 2012 E License (1 Year Subscription), No CD
1 Operating System Microsoft Windows 7 Home Premium with Service Pack 1, 64bit DVD OEM

Coming to a grand total of $993

Or to buy a HP ENVY h8-1425a from JB Hi Fi for $1100 with the following stats:

Operating system
Windows 8 64
Processors
Intel(R) Core(TM) i7-3770
o 3.4 GHz
Chipset
Intel Z75
Memory[ - ]
Memory, standard
8 GB 1600 MHz DDR3
Memory layout
(2 x 4 GB)
Memory slots
4 DIMM
Storage[ - ]
Hard drive description
1 TB SATA (7200 rpm)
Optical drive
SuperMulti DVD Burner
Graphics[ - ]
Graphics
NVIDIA GeForce GT 640 (3 GB DDR3 dedicated)
Expansion features[ - ]
Ports
2 USB 3.0
8 USB 2.0
1 Microphone
1 LAN
1 DVI-I
1 DVI-D
1 Line-out speakers/headphones
1 Line-in line level audio input
1 rear center speaker/sub-woofer
1 surround speakers rear
1 side speakers
Video connectors
1 VGA; 1 DVI; 1 HDMI
Memory card device
15-in-1 memory card reader
Media devices[ - ]
Audio features
Integrated Azalia 7.1 channel Audio; Beats Audio(TM) Studio Quality Sound
Input devices[ - ]
Keyboard
HP wireless keyboard and wireless optical mouse
Communications[ - ]
Network interface
10/100/1000Mbps (Gigabit) Ethernet Support
Wireless
Wireless LAN 802.11a/b/g/n featuring Dual-band (2.4Ghz/5Ghz) 2x2 with Bluetooth 4.0 MIMO technology

I know that what i am supposed to be doing on it won't be a trouble, but my main query is which will be able to run games the smoothest on high settings. The staff at scorptec who recommended the first computer said that it could run any game perfectly on full graphics, would this be the same for the hp? Also which ever is better, could you please tell me the components that make it the better buy?

Thanks!