Time to upgrade my VGA in order to run the newest games.

my modest system is the following:

AMD64 3000+
2GB Corsair DDr Ram
MSI K8Neo4 motherboard
Inno3D GeForce PCX 6600 256MB

my budget is around $200 - i do not want to buy myself a new PC, i just want to run games on medium details at 1024x768 resolution without a pain in the **s

I have the following VGas in mind

Jetway Geforce PCX 8600GT 512MB DDR3 w/TV $175.00
eVGA GeForce PCX 8600GT 512MB DDR3 $193.5 (www.quantum.cc)
Inno3D Geforce PCX 8600GT 512MB DDR3 w/TV $233.00
Inno3D Geforce PCX 8600GT 512MB w/TV $163.00

first question: will they run fine on my motherboard ? (theoricaly they should)

2nd question: there is a ~ $64 difference on final price between Jetway and Inno3D 512MB DDr3 cards and $20 between the Jetway and eVGA... i looked them all up on the internet and they all have same clock speed etc etc

So what is the real difference between them other than the brand name ? I am concerned with performance.. I have used all 3 brands before but i have no real clue which is better performance-wise.

Any suggestion ?

No, i am not an ATI fan