Video card upgrade with questions

[IRanNaked]

I currently have a antec case with a 500W PSU built in. Link: http://www.newegg.com/Product/Product.aspx?Item=N82E16811129158

I have a 20 and 4 pin plug going to my motherboard and i attached a 4 pin peripheral plug onto the cable going tot he mobo so i could run my hd's and dvd burner. I know this isnt the safest choice but i wanted to be able to use my upgrade.

I am thinking about buying a nice 1GB video card, nothing too pricey, and maybe using crosfire in the future.

These are the video cards i am thinking about getting.
HIS H467QR1GH Radeon HD 4670: http://www.newegg.com/Product/Product.aspx?Item=N82E16814161315
HIS H467PR1GH Radeon HD 4670: http://www.newegg.com/Product/Product.aspx?Item=N82E16814161314

Don't know if i need a PCI-Express Connector or not. I would also like to be able to upgrade my PSU directly instead of getting a new case.
The questions i have are, what would be a good PSU to get that is around 600W and what should be better on a "quieter" upgrade. I hate the sound of the whirring fans i had from my last video card and mobo.

Thanks in advance

[XYZ]

You will need a PCI-E connector, as these are indeed both PCI-E video cards. Most currently available power supplies will have provisions for this.

The power supply can indeed be replaced without replacing the case; they only have 4 screws holding them in, but depending on your set-up, you may or may not have to remove the motherboard to remove the power supply. I wouldn't think you'd have to, but no way of knowing without seeing the set-up. Antec sells an "Earth Watts" line of power supplies touted as quieter, and I know they have these in 500W units, as I have 2 of these in computers of my own.

I bought a Radeon AGP video card for a computer with older parts, mainly because AGP cards are getting hard to find new. The one thing I don't like about the Radeon card is that it relies heavily on Microsoft's .NET framework, meaning large, bloated files that you have to have installed on your machine in order for the video card to work. When I tried to cut back on some of the .NET clutter, I got a warning that the card needed these to function properly. Just FYI, if you don't mind that, no biggie, but with that in mind, my future video card purchases will definitely be Nvidia.

[IRanNaked]

Thanks for you response. Now I know I can just buy a better power supply and skip spending money right now on a case.

I have a asus M4A78T-E mobo with ATI Radeon HD 3300 built-in 128MB DDR3 1333 SidePort Memory. I've been reading online that having a NVIDIA Graphic card on this type of mobo will cause a video driver conflict. Hoping when i disable my on board HD 3300 i won't have any problems. You really recommend for me to get a NVIDIA card? I have 2 HD's. One 160GB and another 80GB where i have windows xp on and would like to keep them as empty as possible...

I play games a lot but i build this computer in '06 and someone picked all the parts for me and i have yet to upgrade it so that is what i am doing now. don't know TOO much about components but I'm willing to learn because I've been interested in computers since i first got on a apple in elementary school.

Back to the Power Supply... I was looking online and i see one i like. http://www.newegg.com/Product/Product.aspx?Item=N82E16817148041
Now the fan at the top, does that suck in or blow out air?

This is my set up

Antec PERFORMANCE TX TX1050B with 500w Power Supply
ASUS M4A78T-E AM3 AMD 790GX HDMI ATX AMD Motherboard
AMD Phenom II X2 555 Black Edition Callisto 3.2GHz CPU with all 4 core's unlocked
G.SKILL 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333
160GB Maxtor Maxtor 6Y160M0 (SATA)
78GB Western Digital WDC WD800JD-75MSA3
LITE-ON DVDRW SOHW-1693S DVD+R/RW
MS Windows XP Home 32-bit SP3