Client is complaining that website is big on his laptop [on hold]

My client is complaining that on his laptop the website is big and it cuts off parts of the initial view when the page loads.

I know this to be because his resolution is low. How do I deal with this situation? I have used bootstrap which is an industry standard framework and I have made sure the website works on all devices, but this has just thrown a spanner in the works.

Any advice please