Well there could be several things causing this.
1. Heat of the GPU is getting beyond normal/stable temps. This is very common on laptops especially with GPU acceleration. Most GPU's today have a thermal point in the 95C range. However they get real unstable in the mid 80's.
2. The ram of the system in general is not enough to handle the application usage and the hardware acceleration caching besides the shared ram used for frame buffer. 8GB of ram is honestly really low for the Adobe with hardware MPE on and HD. There is allot of ram being used for the caching of GPU acceleration data since that is how GPU acceleration works. Based on the info above, it sounds like you are reaching a point where the shared frame buffer block of ram is getting used and corrupted by the GPU acceleration blocks of ram. The GPU acceleration memory allocation is going to fluctuate based on caching set by Adobe and also the amount of Frame data/ material caching. I would say this is the most likely issue that you are running into. However the only way to test that is increase the ram and then try the hardware MPE again. BTW the real minimum amount of ram you should have with hardware MPE and HD is 12 to 16GB depending on platform. Any less and you will likely run into problems.
3. Video driver has issues with the current GPU acceleration in use. This could be the case if you running into a driver that has a different Cuda/Opencl version than what Adobe is using. That is easy to check by verifying the last version Adobe has tested with.
4. Last is a bad stick of system ram or a bad video card/GPU chip on the board. This is a possibility however you would likely be seeing other issues with the OS or other applications if so.
Hope that helps.
Eric
ADK
