PC Mechanic looks at HyperMemory and TurboCache, and helps you figure out what’s what.  Along the way they also explain how their can be many different prices and models off of the exact same core.
“Since the release of PCI-Express, the two graphics giants, nVidia and ATI, have picked up their pace of releasing new graphics solutions for all users. Specifically, the innovations of key technologies were not reserved for simply the high-end graphics users. nVidia and ATI started catering more and more to low-end consumers. For most of the graphics card industry’s short life, manufacturers have deemed making a card is too expensive for those who do not have deep pockets. Because of problems associated with manufacturing costs, manufacturers often crippled low-end graphics card chips.”

Here are some more Graphics Card articles from around the web:

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