I generally go by what this site recommends since it breaks the products down into price ranges and they do a lot of benchmarking. They update it every month (not sure why February isn't done yet).
http://www.tomshardware.com/reviews/best-graphics-card,2118.html Best PCIe Card For $115 : TieGood 1600x1200 performance in most games; 1920x1200 in most titles with some lowered detail
Radeon HD 4830 Codename: RV770LEProcess: 55 nm
Universal Shaders: 640
Texture Units: 32
ROPs: 16
Memory Bus: 256-bit
Core Speed MHz: 575
Memory Speed MHz: 900 (1,800 effective)
DirectX/Shader Model: DX 10.1/SM 4.0
The new Radeon HD 4830 finally gives AMD something to compete against the legendary GeForce 8800 GT (as well as its identical sibling, the 9800 GT). Just as the 8800 GT is a crippled 8800 GTS, the Radeon HD 4830 is a crippled HD 4850. Both cards are excellent, while one winning over the other depends on the game or the image-quality settings.
GeForce 9800 GT (aka 8800 GT 512 MB)Codename: G92
Process: 65 nm
Universal Shaders: 112
Texture Units: 56
ROPs: 16
Memory Bus: 256-bit
Core Speed MHz: 600
Memory Speed MHz: 900 (1,800 effective)
DirectX/Shader Model: DX 10/SM 4.0
While the Radeon HD 4830 offers the 8800/9800 GT its first competition in its price class, the card remains a strong contender and is still a viable option. However, it has been reported that some 9800 GTs have been found in the wild with 3-way SLI support.
PCIe Interface: $150 To $240
Best PCIe Card For $150 :Good 1920x1200 performance in most games, some with lowered detail
Radeon HD 4850 512 MBCodename: RV770
Process: 55 nm
Universal Shaders: 800
Texture Units: 40
ROPs: 16
Memory Bus: 256-bit
Core Speed MHz: 625
Memory Speed MHz: 993 (1,986 effective)
DirectX / Shader Model: DX 10.1/SM 4.0
The Radeon HD 4850 is the new people’s champion, instantly bringing yesterday’s $300 performance level down to the mainstream $160 price point. This card has a lot of potential when used on its own, and becomes a devastating force when paired with a second 4850 in a CrossFire configuration.
Best PCIe Card For $170 :Good 1920x1200 performance in most games, some with lowered detail
Radeon HD 4850 1 GBCodename: RV770
Process: 55 nm
Universal Shaders: 800
Texture Units: 40
ROPs: 16
Memory Bus: 256-bit
Core Speed MHz: 625
Memory Speed MHz: 993 (1,986 effective)
DirectX/Shader Model: DX 10.1/SM 4.0
For a few dollars over the base-model Radeon 4850, a 1 GB version is available. While raw performance is not all that different, the extra video RAM is helpful in some situations and with some game titles.
