I wanna buy a new Graphics Card, I have 2 choices:

1.Visiontek Radeon HD 4850 Video Card - 512MB GDDR3, PCI Express 2.0, CrossFireX Ready, (Dual Link) Dual DVI, HDTV, HDMI Support, VGA Support
Specifications
GPU/VPU:
RADEON HD 4850
RAMDAC:
Dual 400 MHz
Additional Features:
RoHS Compliant
HDCP Enabled
HDTV Ready
OpenGL 2.0
Vista Certified
DirectX 10.1
CrossFireX Ready
Game Physics Capable
Maximum Resolution:
2560 x 1600 (Digital)
Video Memory:
512MB
Memory Type:
GDDR3
Core Clock:
625 MHz
Memory Interface:
256-bit
Stream Processors:
800
Interface Type:
PCI Express 2.0
Interface Speed:
x16
Connector(s):
VGA (15-Pin D-Sub)
Dual DVI (Dual Link)
HDTV/S-Video
HDMI (w/ Adapter)
Multiple Monitors Support:
Yes
Visiontek Radeon HD 4850 Video CardThe VisionTek ATI Radeon HD 4850 brings the power of graphics "supercomputing" to gamers, setting a new standard for visual computing. Redefine the way you play and take HD gaming to the extreme with best-in-class performance. The new TeraScale graphics engine delivers an immersive, cinematic gaming experience. Add this GPU to your PC and watch Blu-ray movies and play HD content with incredible visual fidelity.* Do it all with break-through efficiency that doesn't compromise performance.
The ATI Radeon HD 4850 Series GPUs deliver a cinematic gaming experience with unprecedented performance. The powerful new TeraScale graphics will propel you deep into your gameplay with seamless frame rates and high resolutions. Enhanced anti-aliasing (AA) and anisotropic filtering create striking graphics with unparalleled realism so you can max out the settings of the most demanding next-generation games or revitalize your favorite titles. Play today while preparing for tomorrow with tessellation, support for DirectX® 10.1 and scalable ATI CrossFireX™ technology.
Price: $174.99
2. EVGA GeForce 9800 GTX Video Card - 512MB GDDR3, PCI Express 2.0, SLI Ready, (Dual Link) Dual DVI, HDTV

Specifications
GPU/VPU:
NVIDIA GeForce 9800 GTX
RAMDAC:
Dual 400 MHz
Fill Rate per Second:
43.2 Billion pixels
Additional Features:
HDCP Enabled
HDTV Ready
SLI Ready
DirectX 10
OpenGL 2.1
PCI Express 2.0
Vista Certified
Maximum Resolution:
2560 x 1600 (Digital)
Video Memory:
512MB
Memory Type:
GDDR3
Core Clock:
675 MHz
Memory Interface:
256-bit
Memory Clock:
2200 MHz
Shader Clock:
1690 MHz
Stream Processors:
128
Memory Bandwidth:
70.4GB/sec.
Interface Type:
PCI Express 2.0
Interface Speed:
x16
Connector(s):
Dual DVI (Dual Link)
HDTV/S-Video
Multiple Monitors Support:
Yes
EVGA GeForce 9800 GTX Video CardRun challenging games in full force. Intensify your gaming experience to the max. With the EVGA NVIDIA® GeForce® 9800 GTX 512MB graphics card, you can do all of this and more, because it raises the performance bar to another level. This graphics card enables full-throttle lifelike game play at intense resolutions while providing optimal power management with HybridPower™ technology. The PureVideo® HD engine delivers unmatched video and movie quality with spectacular picture clarity, featuring scene-optimized color and contrast enhancement. And when coupled with nForce® SLI®-ready motherboards, it provides amplified performance up to 2x in a dual SLI configuration and up to 2.8x in 3-way SLI mode. Packing more performance at an exceptional value, the EVGA NVIDIA® GeForce® 9800 GTX 512MB graphics card offers you an extreme HD gaming and a first-class entertainment experience.