fluctuate

i have nvidea geforce 84oo gs. I recently updated my driver with latest 169.25. From that time taking 1-2 minute bracke my monitor fluctuate. i have a HCL branded system. my monitor supports resolution 1280*1024@60 Hz. what is the problem here?

I use airtel connection 115 kbps(coonected through cabe (Phone)). my download speed is 3 kbps with IE & fluctuate between 3.5 and 4.00 in FDM. What is this!!!