Here's a simple way of knowing whether your CPU can play Diablo 3. I am using Windows XP, and my name is dannybuntu, so yeah, whatever, anyway.
1. Click on the Start Button, then click on Control Panel
2. Scroll Down and Double Click on System
3. Under the General Tab You Will Find Your CPU Information. Note that
5. Now go to CPU Benchmark
6. Press CTRL+F to find your CPU. For mine I just typed E2140. Note the number beside your processor. My processor is an Intel Pentium Dual E2140 @ 1.60 GHz. It's passmark score is 900.
If your CPU's score is higher than 741 then your CPU passes and you can run Diablo III!!! Hooray. Mine does since
900 > 741
This is not a hard and fast rule, but it will do if you are not very technical. Also take note of the memory, RAM, video card and hard disk requirements. The Open Beta alone, needs 15.1 GB of hard disk space. Good luck and I hope that your system meets and even exceeds the Diablo 3 computer requirements.