buying a power supply for 507gr

ok i have a gateway 507gr , i recently posted a topic about buying a video card for my gateway. i bought this one http://www.newegg.com/Product/Product.aspx?Item=N82E16814102084

it needed a bigger power supply, 350 -450 watts im not sure, but thing is i only got 300watts. im not sure what kind of power supply to get. i am thnking about getting thione of these

http://www.newegg.com/Product/Product.aspx?Item=N82E16817193017
http://www.newegg.com/Product/Product.aspx?Item=N82E16817709011
http://www.newegg.com/Product/Product.aspx?Item=N82E16817170014
http://www.newegg.com/Product/Product.aspx?Item=N82E16817170017
http://www.newegg.com/Product/Product.aspx?Item=N82E16817709012
http://www.newegg.com/Product/Product.aspx?Item=N82E16817193018
http://www.newegg.com/Product/Product.aspx?Item=N82E16817170010



note they are all cheaps ones as i cant spend too much more money on my comp cus my mom is getting pissed at what im spending on my debit card cus im like 15 years old/

heres the link to the gateway site with the current power supply i have
http://support.gateway.com/s/POWER/102544/102544nv.shtml

note that i have limited knowledge on computers and i have never upgraded my psu before,your help will be VERY appreciated.

 

guys please i need help.

 

If I were you, I'd go for a name brand power supply over the higher wattage. This one for example should be just fine:
http://www.newegg.com/Product/Product.aspx?Item=N82E16817371013

If you want some more power, this one is $34.99 with a $10 rebate:
http://www.newegg.com/Product/Product.aspx?Item=N82E16817153023

 

once again, i'd keep your p/s questions to 1 thead (also, your video card - as you have 2 now). as i mentioned (in another thread), i'm sure you need help, but it's very unproductive to have multiple threads. - sos

http://forums.majorgeeks.com/showthread.php?t=158357 <-- wondering if this is enough

http://forums.majorgeeks.com/showthread.php?t=158302 <-- is this power supply compatible with my computer?

 

srry, its just that i am in need of a new power supply badly, ive decided on this 580w power supply

http://www.newegg.com/Product/Product.aspx?Item=N82E16817709012

i compared the connectors with the ones i have and they match up, the size also looks the same too, it got some decent reviews so i plan on getting it, but im not sure if it is enough cus i read something about the 12v rails and that you might need 2, but im not sure can you guys help my on that?