A "high end" laptop in this case would be a multi-thousand dollar laptop designed specifically for gaming. To help compress the size of the laptop, many/most pieces are custom made or fit, making the GPU non-replaceable in most circumstances. In the big honkin' ones you can, but the majority of people who are that into gaming choose a desktop instead. It is possible that your computer would support it, though I wouldn't count on it. If you're handy with computers you could attempt to replace your optical drive with a GPU - I've seen it done before - but at that point the potential dangers generally outweigh the chance of success.