Well, the i7 processor certainly is faster than an i5. Better check the comparisons at tomshardware.com for your prefrerred applications.
Same for the 2 graphic cards. For graphic design surely 2 GB is an overkill already. For games it depends on the game if they see the difference between 2 GB or 4 GB. But since you didn't mention any specific game, nobody can tell what you would see. Note that you might need Windows running on the Mac to play a certain game.
For the RAM most users only need 8 GB. Nothing in your post makes me think you need more, unless the recommended RAM for your preferred games is more.
Unused RAM doesn't make any difference for the performance, although it might increase the lifetime of an SSD.
For the fusion drive see http://www.pcmag.com/article2/0,2817,2412726,00.asp, for example. A 3 TB FD would not be faster than a 1 TB FS nor (for most purposes) slower, but you can store 3 times as much data on it.
Kees
Fairly new to this site, so I don't really know the rules of the forum, sorry X/
I am currently looking for a DESKTOP that is extremely powerful so I could delve into graphic design. I am also an avid gamer so amazing graphics and smooth running of games are a MUST. Price is NOT a huge issue as I am a firm believer in the getting the best products that are well worth the price for my circumstances. I have been eying the 27" iMac with Retina 5K Display and am looking heavily into performance and am wondering if the jumps between these make a real noticeable difference in performance:
3.5GHz i5 vs. 4.0GHz i7 processor
8GB vs. 16GB vs. 32GB RAM
1TB Fusion Drive vs. 3TB Fusion Drive vs. 1TB Flash Storage
AMD Radeon R9 M290X 2GB GDDR5 vs. AMD Radeon R9 M295X 4GB GDDR5
For the storage, I am really comparing the FDs to the 1TB FS, specifically if the 3TB FD would be better than the 1TB FS in terms of performance.
I've been using windows for basically 12-13 years and wanted a change, so I opted for Apple products this time around. However I am still considering Windows products, but as of now I'm really only looking at a Windows laptop (ASUS) which I will buy much later than the desktop. Feel free to leave suggestions though<3
Thanks in advance for reading this novel<3!

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