Why does a 22" monitor have the same resolution as a 20"?

Indeed it will. Not that you’ll really be able to tell unless you spend all day with computer displays, but it is a bit of a cheap one. Go for the 22”, it’ll feel bigger.

The reasoning behind this is display standards for monitors, for dell using the same standard across different sized monitors will save them money in production. Their 20” and 22” monitors use the WSXGA+ standard which is 1680×1050.

Depending on what you are using the monitor for either will be fine, if they were on side by side you could probably tell the image quality on the 20” is better, you will have the same screen real estate regardless. I would base my decision on how good your eyesight is and how far away you sit form the monitor.

The comments above are pretty well spot on.

What video card will you use to drive this monitor?

Radeon ATI HD 2600 XT 256MB

I am planning on using dual 20 or 22 inch monitors that’s why I went with this video card.

I’d go with the 22”. Like Marz said you won’t notice a difference unless you had them side by side.