The Samsung 9100 Pro 8TB is the objective winner of this comparison, securing victories in five out of seven measured specifications. Its most significant advantage over the Samsung 990 Pro 4TB is its storage capacity, which is 100% greater. By offering double the space, the 9100 Pro 8TB provides a substantial increase in total volume for users who require extensive room for their data compared to the alternative.

Users who prioritize maximum storage density should choose the Samsung 9100 Pro 8TB to take advantage of its superior capacity. Conversely, those who are more concerned with the initial cost should opt for the Samsung 990 Pro 4TB, as it holds a 59% advantage in MSRP. Selecting between these two drives depends entirely on whether your primary requirement is the largest possible footprint or a more accessible entry price.