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Hello everyone. Just got a used sager p157sm for a gpu upgrade project and noticed it beeps for a minute then shuts down by itself when under load. It does well when watching movies but when benchmarking the issue pops up. At first I thought it was the gpu so I unplugged it but still occurs. Now it's running only CPU and still does the same things after repasting. Temps of CPU remain along 80 - 87 degrees centigrade. I've cleaned system components and changed Ram modules and slots still nothing. Any help will be appreciated.