Dell laptop freezes every few minutes for a second or 2

For a few days now my Dell Inspiron has been lagging/freezing every few minutes for a couple of seconds.

It seems to be happening no matter what i'm doing on the laptop - playing music, playing a game and even when it's idle. The whole system freezes and if there is audio playing it makes a strange buzzing noise. Any video playing freezes and the mouse freezes too. It is only for 2 seconds at most and isn't effecting the running of the laptop, it's more of an annoyance.

I've run a full scan with Avast! and Malware Bytes. Malware came up clean, Avast! found a few low level things that have been deleted or moved to the chest/vault.

I've also run ChkDsk, which found a few errors and, i'm assuming, fixed them. I left it running over night as it took a few hours to complete.

Any help or advice is hugely appreciated!!

Work through the Troubleshooting Steps for Windows 7 starting with hardware tests, system file checker, establishing a Clean Boot, resolving repeat errors, using System Resources given, and then the other steps which often turn up the problem.

Does the PC still have the factory install? If so that is the worst possible install of Win7 one can have, larded with bloatware and duplicate utilities which interfere with better versions built into Win7. That's why most tech enthusiasts won't even run such an install but instead Clean Reinstall - Factory OEM Windows 7.

Everything needed is in the blue link to get and keep a perfect install just like a million others have done without a single complaint.

Until then you can Clean Up Factory Bloatware.