The Western Digital WD Black SN770 1TB is the objective winner of this comparison, securing more individual specification victories than its competitor. While the two drives tied in the majority of categories, the Western Digital WD Black SN770 1TB holds a significant performance edge in sequential write speeds, which are 17% better than those of the Silicon Power UD90 1TB. This technical superiority makes it the more capable option for tasks requiring faster data transfer rates.

Users who prioritize raw write performance should choose the Western Digital WD Black SN770 1TB to take advantage of its superior sequential write capabilities. Conversely, the Silicon Power UD90 1TB is the better choice for budget-conscious buyers, as it offers an 18% better MSRP. By selecting based on these specific advantages, users can align their storage purchase with either a focus on higher write throughput or a more favorable initial cost.