DOSBox isn't very video intensive so don't worry about it.

Sorry I forgot to indicate why this is important to me. This is important because it is really draining my battery. For example, while under normal use its discharge rate is about -11,000 mW. However, when dosbox is running on any game, the discharge rate can go from -23,000 mW to 33,000 mW!!! This will run my battery out pretty fast! Normally if I am on the road I get 5 hours use of my laptop but at this discharge rate, I will only get 2 hours max! Please help and thanks for your advice.

dosbox is very cpu intensive

You will probably reduce CPU usage by disabling sound in games. OPL emulation, for example, uses a considerable amount of host CPU.

Are you certain that DOSBox is using the NVidia graphics rather than the integrated graphics? I don't know what would be the deciding factor; you could try setting sdl_videodriver=windib in the environment, but this is just speculating on what might work.

Thanks for the reply. I tried Win DIB but Nvidia is still engaged. I know dosbox is very CPU intensive but should not be engaging Nvidia. I saw in the previous DFend version where yhkwong version was not included in the package it did not engage the Nvidia card. Is there any way we can disable or selectively enable Nvidia card when required?

You could try disabling the graphics card through device manager and re-enabling it when needed.

Thanks Dosfreak! I will try it in the morning and report back. Thanks.