time for a new desktop pc.

the last one i built was in 2005 and i haven't really followed up with hardware since.

i'd like to play some (newer) games and be able to stream HD shows/movies/sports to my TV (so I can avoid buying a ps3/360/apple tv) without running into performance problems. my current laptop is super sluggish when i'm doing stuff on the side while streaming which is very annoying. oh and i plan on re-using my samsung syncmaster 226bw screen.

so the parts i put together are gonna run me about 900-950 EUR total. i would've liked to stay closer to 800 EUR but i don't really wanna cheap out and bitch about it later on.

couple of questions right away:
- is the mainboard ok or will a cheaper one be good enough? i basically chose this one because it has a ton of USB ports etc... for phones, external hdds, cameras etc.
- should i maybe get an i5-3470 + cheaper h77 mainboard over of a 3570+z77 combo (planning on overclocking it) and try to get a deal on a better gfx card instead?
- a 480w power supply should do, right?
- not sure yet if i wanna use win7 or win8. the last windows OS i used was win2000...

CPU: Intel Core i5 3570K 4x 3.40GHz So.1155 BOX ~ 200,00 EUR
Mobo: Gigabyte GA-Z77-D3H Intel Z77 So.1155 Dual ~ 105,00 EUR
GFX: 2048MB Sapphire Radeon HD 7870 Aktiv PCIe ~ 205,00 EUR
RAM: 8GB G.Skill Ripjaws DDR3-1600 DIMM CL9 Dual ~ 35,00 EUR
CPU cooler: Thermalright HR-02 Macho Rev.A (BW) ~ 35,00 EUR
power supply: 480 Watt be quiet! Straight Power E9 CM ~ 80,00 EUR
HDD: 1000GB Seagate Barracuda 7200.14 ~ 65,00 EUR
SSD: 128GB Samsung 830 Basic Series 2.5" (6.4cm) ~ 95,00 EUR
tower: BitFenix Shinobi USB 3.0 Midi Tower ~ 50,00 EUR
bluray player: LG Electronics BH10LS38 Blu-ray Disc Writer ~ 70,00 EUR

lemme know what you think. thanks.