Perhaps you can't decide which CPU to buy, you can make a decision after reading the full test Intel Core i9-7900X Cinebench r20 score multi and single core and decide is it a good CPU or a bad one to buy, how powerful is this processor. Here is all information from Cinebench r20 benchmark. A careful analysis of all the technical characteristics, to make it easier to understand, is made by the table. After looking at the data of parallel test and video, you already be able to understand do you need to buy Intel Core i9-7900X or not.
Although it should be understood that all the data in the table above do not mean that you should be guided entirely by them and trust a simple quantitative comparison. Be sure to watch the testing video and read the opinion of of people who bought Intel Core i9-7900X before making a selection buy this processor or not.