Suitable graphics card for 120Hz monitor?

Just bought the Viewsonic VX2268wm 22" monitor which allows 120Hz refresh rate (good for gaming, watching HD video and easy on the eye). When i connect it to my desktop pc i am able to select 1680 x1050 @ 120Hz but this makes the screen go all blurry, i have to select 60 Hz (same res) to get a clear display. Am i right in thinking that my graphics card is not 120Hz compatible? I currently have a 512mb XFX ATI Radeon HD540 installed. I am using the supplied dual DVI cable to connect the monitor to the pc. Do i need something like a NVIDIA 9800 GT?
http://www.scan.co.uk/products/512mb-gainward-9800gt...

Post deleted by camieabz

Nah, its not supposed to be like this. Just wondering whether you only get 120Hz refresh rate with 3d capable cards such as the GT 9800 series. Will give Viewsonic technical support a call in the morning.

Hence I deleted it. It wasn't until I threw in the link that I saw the Geforce bit. (I saw the 540 bit first).

I can't say I've ever seen the results of a higher refresh rate on a monitor over a gfx card. Have you got the manual? Can you get other rates above 60, but below 120?

A better dual-link cable imo.

Even though i can select 100, 110 or 120 Hz rates, choosing any one of these causes the text to go blurry. Only selecting 60 Hz fixes this. In the manual under requirements for 3D Stereoscopic gaming it says:

1) Viewsonic VX2288wm monitor

2) NVIDIA GeForce 3D Vision Kit

3) Compatible NVIDIA Geforce GPU
-Geforce 8 series (Geforce 8800 GT or higher)
-Geforce 9 series (Geforce 9600 GT or higher)
-All Geforce GTX 200 series

4) Microsoft Windows Vista 32 bit or 64 bit

5) Standard Microsoft Direct X Game

In reply to a post by 12eason:

A better dual-link cable imo.

Surely a dual DVI cable is like a HDMI cable...either it works or it doesn't? According to this forum, no-one's had any trouble with the supplied dual link cable.
http://hardforum.com/showthread.php?t=1397927&highli...

Well, I'd say the same for the GC, either it does 120hz at that res or it won't. It wouldn't put out a blurred image. If anything is going to lead to degradation it's going to be the cable imo. Saying that, it could be a setting or fault on the TV too.

The features and overview section state 120Hz, but when looking at the specs:

VIDEO INPUT

Digital DVI-D DualLink
Analog RGB Analog(75 ohms, 0.7 / 1.0 Vp-p)
Frequency Fh=24-82 kHz ; Fv=50-75 Hz
Sync Separate Sync / Composite Sync / SOG

That gives 75 Hz maximum ... which would explain the blurriness, Definitely time to call Viewsonic

Ok called Viewsonic, they said my GPU is not a dual-link video card, i would need to upgrade my GPU. Also if you have a look at the user guide on page 16 under resolution its says that 120Hz is only supported by dual link video cards. I guess that's how 120Hz works by using 60 Hz x 2 links in a dual link DVI. Anyway i've ordered the Asus 1GB Silent GeForce GT 240 DDR3 NVIDIA Graphics Card, probably an overkill as i don't do much gaming (i mainly watch HD movies) but hoping it will last me quite a while.
http://www.scan.co.uk/products/1gb-asus-gt-240-silen...

Thanks for your help