Legitimate "repack" groups (such as the well-known FitGirl) do compress games significantly, but they operate within the laws of physics. A "highly compressed" repack of a 45GB game might shrink it down to 20GB or 15GB. It will never shrink it to 300MB. The mathematics of data storage simply do not allow for a 150:1 compression ratio on binary data without losing 99% of the content.
: Since FIFA 17 is an older title, you can often find physical PC discs at very low prices through reputable second-hand marketplaces like eBay. Technical Requirements for fifa 17 highly compressed pc downloadl free
Before you press download, it's important to understand the landscape. . It has been delisted, meaning the only way to play the game today is via physical copies (if you have an optical drive) or downloaded copies. Legitimate "repack" groups (such as the well-known FitGirl)
