Solid state drives have been gradually falling in price for years, even the best NVMe SSDs, so sudden drops in price are rare. It's even more rare to see a drop as major as this one. The 4TB version of Samsung's 860 QVO SSD is now just $399.99 on Amazon. Not only is that a whopping $150 off the original MSRP, but it's over $100 cheaper than every other 4TB SSD.
The Samsung 860 QVO drives were first released late last year, and they're designed as replacements for high-capacity hard drives. They're not as fast as high-end SATA SSDs, like the Crucial MX500 or Samsung 860 EVO, but they're still significantly faster than spinning hard disks. Our friends at Tom's Hardware reviewed the 1TB model, if you're interested in a more detailed analysis.
Amazon appears to be the only retailer selling the 4TB drive at this price. You can grab it from the link below.
If you missed this one, then there are always the Black Friday SSD deals to look forward to in November.