Since your brothers may do some CAD which requires good CPU and GPU, I would recommend this ASUS ROG Strix G16 because it comes with i7-13650HX CPU which is one of the best in your budget and great for your usage, 32GB of RAM for smooth multitasking, Good SSD storage of 1TB for faster boot up and loading, 16'' WUXGA 165Hz screen which is a must have for this price range, it comes with RTX 4060 GPU, and high build quality.

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