[Build Help] Newbie feeling a bit lost on what parts to pick.

Hello swede here. Old computer broke down about a year ago I've been saving up money to build a new one. The main focus is gaming but it will be used for many other things like Photoshop, programming and i want to try some 3d work.

I've been looking around at Tomshardware and sweclockers and the only components im confident about so far is the CPU and the GPU.

i have almost 16000 SEK (2 500 dollars) available

This is what i think so far

CPU: i5 2500k

HDD: SSD around 100Gb for operating system HDD x 3 2TB each and going for raid 5. other then size i don't know how interpret the stats. how would having HDD on diffrent SATA ports Speeds(3 and 6 Gb/s) effect raid?

RAM: i was thinking somewhere above 8Gb probably 16

GPU: 570 GTX I'll add another later on.

CASE: i have no idea what to look at other than i should have enough hard drive slots. I don't really care about how it looks.

PSU: i haven't looked at this yet as i don't know how much power i need until i know what other parts i want.

MOTHERBOARD: ASRock Z68 Extreme4 Gen3 going of a review from tomshardware but I'm still feeling kinda uncertain about it.

Monitor: uncertain what to look for. I want 1680 x 1050 as max resolution, what other Criteria should i have?

OS: i'm going to dual boot Debian and windows 7

I'll continue my research, Any pointers to good sources?