A. I recently started using Prime95, which is a great utility to stress all the cores on a CPU. As you can here, it works great and stresses the computer to its limit.

Click to expand.

You can download Prime95 from this site. There's also a 32-bit version available.

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Check out hundreds more useful Q&As like this in John Savill's FAQ for Windows. Also, watch instructional videos made by John at ITTV.net.