I had the exact same problem as you. I was about to purchase a eVGA 7900GT when I noticed my old (2003?) CRT monitor could not be hooked up to it. Fortunantly, most video cards with DVI monitor ports come with an additional adapter thing (with the older D-Sub hook up on it) that you attach to the DVI port and then hook up to the monitor. If you're buying off the internet, look at additional pics of the product. It will show these adapters if the product comes with them. If you don't see them, go to www.newegg.com and get a 7900GT from eVGA. I'm sure these GPUs come with the adapter that you need.
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