Try Real Temp - CPU temperature monitoring
It can monitor your video temperature too, in most cases. That may be a problem on a laptop, though.
As for the video, that would be a BIOS setting. If you have plenty of System RAM you can allocate more of it to the video subsystem - sometimes much more.
From the specs, it looks like you have plenty of built-in video memory. I'd pursue the temperature and driver
issues. If this is a brand new laptop and you have good airflow around it it shouldn't be too dirty inside. What video driver are you using?