I'm getting close to buying a Ratel Performance, configured like this:

Intel Core i7 3770 (3.40GHz - 4 cores with hyper-threading, HD Graphics 4000)
Dedicated GPU: 1 GB nVidia GeForce GT 630
Hard drive: SSD

Intended usage: mainly for writing, web surfing, email, etc., some graphics (GIMP) and occasionally ripping CDs or other intense use (but probably just short periods of intense use). This would be my main desktop machine. Ubuntu 12.04 only.

Questions: Will a dedicated GPU make much difference with the Ratel configured this way? (SSD, fast processor, HD Graphics 4000.) Will there be noticeably better rendering - or are there some advantage(s), other than cost, in getting just the integrated graphics and skipping the GT 630?

Would the dedicated graphics card make the machine run hotter or cooler? - or doesn't this affect the temperature very much?

And speaking of heat... Does the Ratel tend to run hot, cool, or just average temps? Does it have a noisy fan?

I'm hoping to save some money, and have more SPACE in my work area, by going with the little Ratel P. - but maybe this is a bad idea, and the Wild Dog P. would be a better choice, despite the extra cost and the large size. What do you think?? Any advice would be highly appreciated!