Former graduate student,
The short answer your question is "yes". Admissions officers have to go through hundreds, if not thousands of CVs each year and while they would ideally spend a good few minutes with each CV, this is not the case, at least with bigger schools. Hiring managers (and probably admissions officers as well) will usually spend less than 30 seconds with each CV, so it's important that they see the important points within this short time frame. It never hurts to have your CV be aesthetically pleasing, at least in terms of formatting. If you're looking at the 60th CV for the day, you wouldn't want to even look at a CV that has poor formatting, right? That's why it's intrinsic to place your strongest and most important points of your CV at the top, where the reader is likely to see it first. If an item catches their eye, that's where your descriptions and supporting points back up the first item that caught their eye in the first place.
CVs need to be concise and directly to the point, with the strongest points at the top. Admissions officers do skim over CVs, and so formatting is quite important. The most important part of a CV is the content, followed by the format. What good is an amazing CV if it's in a format that nobody wants to read? If you're looking for a clean format to use, I would recommend finding a nice, professional-looking format on Google and using a template that you like.