ADATA SU650 512GB SSD vs SanDisk Optimus 5100 4TB NVMe SSD

The SanDisk Optimus 5100 is the far faster drive: PCIe NVMe in an M.2 2280 stick, rated up to 6,900 MB/s read and 6,700 MB/s write, with 4 TB of capacity. The ADATA SU650 is a 2.5-inch SATA drive at 520/450 MB/s and 512 GB, so it suits older laptops and desktops with a SATA bay and nothing else. Buy the SanDisk for any machine with an M.2 slot, especially for large game or media libraries. Buy the ADATA only to revive a SATA-only system on a budget, and expect roughly a tenth of the sequential speed.

• Choose the ADATA SU650 if your machine has only a 2.5-inch SATA bay and you need a cheap, simple boot drive for an older laptop or desktop.
• Choose the SanDisk Optimus 5100 if your board has an M.2 2280 slot and you want top-tier speed and 4 TB of room for games, video or large project files.