Are there any newer drivers for the GPU?
If not, please run Furmark
*** WARNING: Unable to verify timestamp for igdkmd64.sys
*** ERROR: Module load completed but symbols could not be loaded for igdkmd64.sys
Run Furmark to test your GPU. Furmark tutorial
Run Furmark for around 30 minutes
Your GPU temperatures will rise quickly while Furmark is running. Keep a keen eye on them and abort the test if temperatures rise too high
Please note the temperature of the GPU when idle and under load.