The textures have 100 times more details, items have way more polygons and everything is just better, so either you might want to consider an optician if you can't see it or you are playing on low settings.
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You can flash your 4,1 to 5,1 they are 99.9% identical - I did it with mine and it's not hard at all - it also means you can upgrade your CPU with a faster one - there are plenty on ebay for pretty cheap.
http://forum.netkas.org/index.php/topic,852.0.html
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Seems like you don't know what vaporware means.