The n3ds has a faster cpu than the o3ds, it also has an l2 cache that the o3ds doesn't have. The options are for n3ds only and do nothing on the o3ds.
The games that are made for the o3ds don't take advantage of the new 3ds's power. The options let them. It can help to remove or eliminate fps drops in the games and make them play smoother.
What an l2 cache is
http://www.pcmag.com/encyclopedia/term/45870/l2-cache
So if I have a N3DS is this something I should use? Will this change the speed of games, or just make them look nicer? Should I check the clock+L2 box?
