How to diagnose repeated freezing of Windows 7 (comes back alive for a few seconds)

I installed Windows 7 in a 3-year-old machine. It installed successfully, took all drivers and running great, but every 5-6 minutes it freezes for a few seconds... 30 seconds to 1 minute, and then it comes back alive.

I checked Event Viewer, but nothing matched the frozen timeline.

I would appreciate any help on how to detect what is causing it, service or hardware.

After it comes alive, everything runs normal. I did run Task Manager and checked CPU usage, at the time it freezes just before and after that no task took more CPU or memory. It was like an idle machine.

There aren't any external USB drives or devices. It is an on-board Intel desktop board with SATA HDD, and the SATA HDD is running in absolute good mode.

Download and run MooO System Monitor.

It will immediately issue a 'bottleneck' warning as spikes occur and 'name and shame' the culprit.

Download Process Explorer and run it.

Next, wait until the next spike and click on any of the three graphs at the top. You should be able to see peaks. When you hover your mouse over any of them, it should be able to say what process is hogging your CPU.

If there is nothing, you may want to reinstall Windows 7 / Uninstall any drivers you may have as they could be corrupt/bad.

All I had to do was uninstall NOD32 Smart Security v.3.

As far as I have understood on some systems, the Windows Defender software isn't all that compatible with "active protection" solutions (and Windows 7?). I never came to test disabling it and testing, but as the computer is running fine now with VIPRE I'm kind of satisfied.

These kind of problems often come from bad drivers. I installed a new chipset and ATI drivers and voilà! No more problems. Let’s hope it stays that way!