I have a laptop with those exact specs so I went ahead and tested on the manta boss. With EFB -> RAM, 1X internal resolution, and tried the intro and it ran pretty smoothly. It dipped down to 22 fps but I'm on the PAL version and that would be like 26 fps on the NTSC version. Also, it didn't dip much honestly, maybe twice. Besides that it ran smoothly at 25 fps. Give me some cut scenes or parts of the game it's slowing down on and I'l try them and make sure your laptop is on high performance mode.
Gaming Rig
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