its just a selling point. a lot of board manufacturers will say things like that, even tho they know full well it's not feasible. 

did you research the board before you bought it? i always look for user reviews.

a few other points you should note. onboard graphics is generally a (very) bad idea when building a machine that's intended for gaming or graphics work (especially fast render times, as you stated is your goal). they're never as powerful as having a dedicated graphics board with its own ram, and usually always cause problems. onboard graphics will pull system resources that a seperate graphics card will contain on its own. 

even if you do manage to get 32 gigs in it, combined with a quad core processor, your heating issues will be insane unless you have some serious air flow and/or a liquid cooling system in place. judging by the fact that it's a micro board, I'm guessing you're putting it in a micro case. Even at just 16gb of ram you're still likely to have heating issues in a small case.

this board is intended for office work. good for word processing, data, web browsing, etc. not good for graphics. 

8gb of DD3 is really not much better than 8gb of DD2. You'll see some minor improvements but really not much, and since the onboard graphics will be pulling a portion of that ram, it's likely it will be slower than the build you have now. 

If you haven't had it for long, it's possible you could exchange it for a better board. Depending on your budget, that would be my recommendation.

 

~Shane