Here is what happened:

I installed the Diablo 3 Beta client and played through once without any real problems at all.
The next day, I reformatted my computer, so I redownloaded the beta client, which fully installed without any problems. However, now I am receiving an "Unsupported video card" message every time I try to start the game. My video card is a Geforce GTX 550 Ti, which I was using just yesterday to play just fine. Anyone else have similar problems?

TheJawbone,

This is due to a bug in the game right now. It will often misreport a compatibility issue with most Nvidia cards for users on Windows XP. The simple workaround is just to hit the escape key when the warning message appears.

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