I’ve been currently developing my game on a top of the range PC which runs the game at 60 fps but when I tested it on my low end laptop I experienced major lag running at 15 fps. I figured out that when I ran the game in the lowest resolution it was able to run at 45fps. I assume this means it isn’t a problem with the draw calls, physics or scripts. So what could be causing the lag?
I’ve taken a screenshot of my game running with the profiler visible:
https://picasaweb.google.com/lh/photo/6Gj_RTZRHs7odweb2w4HgNumTc6NW7XejYB1ytE8p7o?feat=directlink
Your problem is probably that your low end GPU just isn’t fast enough for the required fill rate. A larger resolution requires a greater fillrate. Keep in mind that fragment shaders are executed for each pixel. So the larger your resolution the more pixels it has to render. If you have a lot of overdraw it even gets worse. Keep in mind that if you double the resolution you actually have 4 times the pixel count. It’s a quadratic increase.
Hello,
Please ensure that you’r laptop is in the high performance mode. If this wont help then you can check if there is problem with choosen GPU. Many games uses integrated graphics when run on a laptops even though you have a “super-ultra graphics chip from nvidia”.
If that wouldn’t help, just leave the comment and i will make some research 
Regards,
M. Rogalski