Try updating your graphic card drivers to the latest ones. Go to Options, Work Enviornment, click Graphics. Ensure that OpenGL is selected for 3D rendering and that Hardware Acceleration is enabled. Couple more things you can check is to check memory settings in Options, Preferences and click Memory and Cache, adjust the memory allocation higher if its too low. Check if your laptop is in battery saving mode which throttles performance to save power. Upgrade your windows to latest update and last thing you can check also is to see in task manager what is you CPU, GPU and RAM usage while working with elevations and worksheets. Give feedback after you try these thing so i could try to help you a little bit further about the problem.
P.S. It may sound stupid, but using 32bit version of AC also could cause those problems so check also which BIT version you are using.
