laptop problems

Hi,

Since I have my laptop, almost a year now, I've been having some lag problems. While playing ET/CS my laptop randomly lags for a few seconds. In ET, I easily reach my 125fps and 48 ping, but every now and then my ping jumps to 300 and my screen is laggy. Then it's back to normal again. At first I thought it was Windows Wireless Zero scanning for internet connections, but I set that value to 0 in the registry AND I tried cable internet and both didn't solve my problem.

I think all my drivers are up-to-date, so what can cause this problem?

Thanks in advance.