Harold has a home-built computer and he's getting an annoying and long system beep when he runs video applications. Leo says a long beep is usually an indication of a temperature issue. The thermal paste on the processor could have been misapplied and it may not be dispersing the heat as efficiently as it could.
If that's not the issue, he can go into the BIOS and check the settings for his temperature alarm. He shouldn't change the temperature too much though or he may damage the computer. Make sure there's nothing blocking the air flow. Even with a bunch of fans, air flow could be restricted in the computer. He should do a Google search for his AMD CPU and check the thermal rating. That will tell him how hot it should get, and he should make sure not to let it get any hotter.