Need Advice First build Steam Machine $800 budget

[Hammersmith38]

I have never made a pc before and am just starting my research.

Approximate Purchase Date: Late Spring Early Summer 2014

Budget Range: ~$800 After Rebates

System Usage from Most to Least Important: Gaming, Media Center, Web Browsing
Parts Not Required: Monitor, Mouse, Keyboard I just need help picking parts for tower.


Country: USA

Parts Preferences: by brand or type
I want to use the BitFenix Prodigy case, Otherwise I just want Best bang for the buck and something that will last as long as possible.
Overclocking: Maybe

SLI or Crossfire: I don't know that that is.

Monitor Resolution: Not sure yet.

http://pcpartpicker.com/user/Hammersmith38/saved/3Gah

 

[realchaos]

PCPartPicker part list / Price breakdown by merchant / Benchmarks

CPU: Intel Core i5-4430 3.0GHz Quad-Core Processor ($184.29 @ Amazon)
Motherboard: ASRock H87M-ITX Mini ITX LGA1150 Motherboard ($94.99 @ Microcenter)
Memory: Crucial Ballistix Sport 8GB (2 x 4GB) DDR3-1600 Memory ($74.99 @ Microcenter)
Storage: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive ($59.98 @ OutletPC)
Video Card: MSI GeForce GTX 760 2GB Video Card ($239.99 @ Amazon)
Case: BitFenix Prodigy (White) Mini ITX Tower Case ($74.98 @ OutletPC)
Power Supply: XFX 550W 80+ Bronze Certified ATX Power Supply ($49.99 @ NCIX US)
Total: $779.21
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2014-02-09 18:22 EST-0500)

Overall stronger in games.

 

[Hammersmith38]

Forgot to add this:
I am thinking of using Windows 8.1, I have heard there is a lot of backlash, but mostly with the UI and Because I'm coming from Apple, the fact the the UI is different doesn't bother me. Maybe there are more issues with 8.1 that I'm not aware of... if so let me know if I'm making a huge mistake.

I may be slowly acquiring parts over the course of this spring... OR if there is something coming out soon should I wait and buy it all at once.

Are sound cards important any more, 10 Years ago I thought about building and I remember looking at sound cards and they seemed like a big deal back then, how about now?

 

[Hammersmith38]

PCPartPicker part list / Price breakdown by merchant / Benchmarks

CPU: Intel Core i5-4430 3.0GHz Quad-Core Processor ($184.29 @ Amazon)
Motherboard: ASRock H87M-ITX Mini ITX LGA1150 Motherboard ($94.99 @ Microcenter)
Memory: Crucial Ballistix Sport 8GB (2 x 4GB) DDR3-1600 Memory ($74.99 @ Microcenter)
Storage: Seagate Barracuda 1TB 3.5" 7200RPM Internal Hard Drive ($59.98 @ OutletPC)
Video Card: MSI GeForce GTX 760 2GB Video Card ($239.99 @ Amazon)
Case: BitFenix Prodigy (White) Mini ITX Tower Case ($74.98 @ OutletPC)
Power Supply: XFX 550W 80+ Bronze Certified ATX Power Supply ($49.99 @ NCIX US)
Total: $779.21
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2014-02-09 18:22 EST-0500)

Overall stronger in games.

THANKS!!!