Building a mid range pc

I was wondering if this build would work and be the best price for someone who is 15 and does not know that much about computers, beside from the razethew0rld youtube channel.
I know the monitor, keyboard and mouse are not very good but I intend on replacing them next year.
here is the list: http://www.amazon.co.uk/gp/registry/wishlist/3IE67G9DB94F/ref=topnav_lists_3 

first things first, you only need 8GB of ram, assuming that you are only gaming which it sounds like you are if you are 15 and don't know much. Use the difference in RAM cost to get yourself a 7870.

Ok, thank you I've changed to 8gb of ram now, with the 7870 and saved £30 

what's your budget?

around £800 

Get the 7950, the 8350, 8gb at 1866 mhz if you can.

http://uk.pcpartpicker.com/p/1z5Q2

CPU: AMD FX-8320 3.5GHz 8-Core Processor (£113.99 @ Aria PC)

CPU Cooler: Cooler Master Hyper 212 EVO 82.9 CFM Sleeve Bearing CPU Cooler (£22.85 @ CCL Computers)

Motherboard: Asus M5A99FX PRO R2.0 ATX AM3+ Motherboard (£109.99 @ Amazon UK)

Memory: A-Data XPG Gaming Series v2.0 8GB (2 x 4GB) DDR3-1866 Memory (£41.40 @ Amazon UK)

Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive (£48.36 @ CCL Computers)

Video Card: MSI Radeon HD 7950 3GB Video Card (£185.75 @ Scan.co.uk)

Case: Fractal Design Define R4 (Titanium Grey) ATX Mid Tower Case (£75.98 @ Aria PC)

Power Supply: XFX 550W 80 PLUS Bronze Certified ATX12V / EPS12V Power Supply (£49.85 @ Aria PC)

Monitor: Asus VE247H 23.6" Monitor (£123.00 @ Amazon UK)

Keyboard: Logitech Desktop MK120-TAA LOG920004218 Wired Standard Keyboard w/Laser Mouse (£32.06 @ PC World Business)

Total: £803.23

ok, thank you. I have never used aria PC before, do you know how reliable they are? Have you ever bought anything from them before?

 

Yes ive used aria pc before there just like buying from ebuyer.