Need advice for 450$ gaming rig

GTS 450 says: Minimum 400W or greater system power supply (with a minimum 12V current rating of 22A)

Your PSU says: +12V@18A. Your PSU also does not have a PCIE power adapter so you are very limited to what graphics cards you can handle. An older 400W PSU would even be questionable with a 5670. Replacing the PSU is something you better plan on if you want a gaming graphics card.

Gigabyte 770T-USB3 motherboard ($80) <has USB3>
http://www.newegg.com/Product/Product.aspx?Item=N82E168...
Athlon II x3 CPU ($75)
4GB (2x2GB) DDR3 RAM <like you linked> ($85)
ATI 5770 ($140)
http://www.newegg.com/Product/Product.aspx?Item=N82E168...
Seasonic 500W 80+ bronze CPU ($53)
<any ~500W Antec, Corsair, Seasonic PSU>
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

I think that fits into your price range and will be a good gaming machine.

regarding the mobo i think i might have found the wrong one on newegg, on the danish sites i'm planing to buy it from it is called "MSI 770-C45" and not "MSI 770T-c45) and acording to 4 different danish sites it does support DDR3

Harddisk space i don't really need 750gb but it only costs 10DKK (roughly 1-1.5$) more then the 500gb so i might aswell just take the estra 250gb, but i'll consider a samsung spinpoint f3







i did NOT notice that, thanks, that would have been anoying to find out that it wasn't able to run  




Is USB3 really worth it ? i don't really use USB that much

Is it better to downgrade the CPU over the GPU it seems like a bit sacrifice. Athlon II x3 is basicly the same clock but one less core and no L3 cash

In Denmark the GTS 450 and HD 5770 are basicly the same price a difference between 10-15DKK(1-2$) or so advantege nvidia card beeing the cheapest actually.

and PSU, basicly just ANY 500watt with 22A@12v rail will be just fine ?

Here is a link for the "right" mobo: http://www.newegg.com/Product/Product.aspx?Item=N82E168... it supports DDR3  

Regarding the 500w PSU with 22A or highter on the 12V rail does anyone have anything good of bad to say about this one: http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Since youre not playing hardcore games, dont get a crappier CPU, that wouldnt make any sense.

Yeah go with a 750GB, just get the Spinpoint F3

USB 3.0 is still brand new, stuff is just rolling out with it, not a necessary option at all

Silverstone seems to get good PSU reviews. This may not be the exact model, though.
http://www.jonnyguru.com/modules.php?name=NDReviews&op=...

With so many USB devices (digital cameras, smart phones, mp players, external backups, etc). I think USB3 doubling the upload/download speeds of these devices is likely to become valuable in the next couple years. Far faster than SATA3 will become useful.

There is no spinpoint F3 750GB. It has 500GB platters so you can get 500GB or 1TB. Thats also why its much faster than a 750GB HDD with three 250GB platters. Denser platters means the head reads more in the same amount of spin time.

If you look at the Toms "Best Gaming CPUs" articles for the past year. The Athlon II x3 has been on it every time. An athlonII x3 and a 5770 will beat a Phenom II x4 and $80 graphics card in any game. The GPU increase gives you a ton more performance than an extra core. Unless you have some scientific uses that would make a 4th core useful, it wont do you any good to get anything more than an Athlon IIx3.