Solved Nvidia GT525M issue in Dell Inspiron Core i5

I bought a Dell Inspiron Core i5 with Nvidia GT525M 1GB laptop like a week ago. I can play games like Battlefiled 3, Need for speed The Run and Ghost Recon Future Soldier without a problem. But the thing is, Sometimes, these games lag on me. And when i do a restart everything comes back to normal. This issue never stops. Any ideas about this issue? (and when i play games, i'm switching the power plan to high performance). Thanks.

Fill out your system specs, please.

Dell Inspiron 15R Core i5 2450M CPU @ 2.50 GHz
Nvidia GT525M 1GB VGA
4GB RAM
500GB HD
Windows 7 Ultimate x64

Dxdiag information is attached...

Got it sorted out. I installed the video driver for GT525M from the Dell site it self (which was an older driver) and when i opened the Nvidia control panel, i saw under "3D settings", under "Adjust image settings with preview", "Let the 3D application decide" is selected. Before, "Use advanced 3D image settings" was selected. I think this caused the issue. Can play everything without a lag now. Thanks guys. Hope this helps.