I have recently installed the full 64 bit version of Windows 7 on to my home PC. Everything has gone smoothly for the first week or so but yesterday a strange problem started happening. Every 30 minutes(on the dot!) the speaker on my motherboard will give two, short beeps. This has been going on for a day now and is getting very annoying; the problem never happened when I was running on XP and only began with the upgrade to 7. The only additional software that has been running at the time of the beeps has been IE and avast, both of which I have tried disabling the sound with no results. I have also opened the task manager and checked to see if any processes have spiked in CPU usage at the time of the beeps... didn't get any results here either. Any ideas and help is much appreciated! EDIT: furthermore, it happens in a fresh boot of safe mode too. Also, I have looked through the event viewer and nothing is being logged during the beeps.