Help with choosing parts for a new budget gaming computer

[freddy1112]

Hi everybody, I'm looking to upgrade from my laptop and id like to build a tower since its cheaper than buying a new one. I'm not familiar with computers or what their parts do so i need a lot of help with picking the components that fit my budget. I have a budget of $600 Canadian, but i can stretch it to $800 if needed. I only play league of legends right now, and plan on playing guild wars 2 when it comes out. I have an old sony vaio desktop that i got in 2005, i doubt i can use much from it other than the cd/dvd drive, and hdd (i put a new seagate 1tb hdd drive in a few months before i replaced the computer). It has no power supply since i gave it to my aunt, since her's broke. I did my best to pick some parts but i am entirely clueless with computers pats and their specifications. I also have a windows 7 os install disc. I'm in rush to build it either, i can wait until Christmas if that means i can get better deals since my laptop is pretty good.

intel core i5-3570 http://www.tigerdirect.ca/applications/SearchTools/item-details.asp?EdpNo=2983973&CatId=1969

evga geforce gtx 560 2gb ddr5 http://www.tigerdirect.ca/applications/SearchTools/item-details.asp?EdpNo=555358&CatId=3669

thermaltake v3 black edition http://www.tigerdirect.ca/applications/SearchTools/item-details.asp?EdpNo=5520044&CatId=1509

DiabloTek PSUL775 775watt http://www.tigerdirect.ca/applications/SearchTools/item-details.asp?EdpNo=924925&CatId=2533

I left out the motherboard and ram since i honestly have no idea how to pick those out. Any help or advice would be greatly appreciated.

 

[allanitomwesh]

Asrock z77 pro 4 motherboard
Intel Core i5 3450 (you don't loose performance but save cash)
G Skill Ares 8gb (2×4) ddr3 1600mhz ram
Zotac AMP! gtx 560ti
xfx 650w pro core edition
Thermaltake v3/corsair 300r case