opengl – Not clearing FBO’s Texture error in battery economy mode

When rendering inside a FBO’s texture, I’m not using glClear() but overwriting each fragment, GL_BLEND is set to true.

This works just fine, but I just realised when my laptop switch to economy mode, and I guess switch to egpu (intel 630) , the texture is full of garbage data when drawn.

here you can see first the working render, and then the garbage one. It should be exactly the same the only difference is my laptop is not plugged in AC

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