Samsung released its latest 2.5-inch SATA SSD today, the 870 Qvo, which comes in capacities up to 8TB – twice as big as the largest 860 Qvo model released in 2018 and substantially bigger than most hard drives. It’s an impressive milestone, even if UK pricing for the largest 8TB model is nearly £800. Still, with game install sizes ballooning out of control – I’m looking at you here, Warzone – a massive new SSD could be just what the doctor ordered.
So how have Samsung produced a 7mm tall SSD that packs in so much storage space? Unlike most of Samsung’s drives, the Qvo series uses QLC NAND, meaning it stores four bits per cell instead of two (MLC, used on Pro series drives) or three (TLC, used on Evo series drives). That, combined with vertical stacking of the flash memory modules, allows the Korean to offer higher capacities than would otherwise be possible for a given price or form factor, which has lead to the existence of that flagship 8TB model.
One downside of 4-bit flash memory though is that random reads and writes can often be quite a lot slower than you’d expect from 2-bit or 3-bit memory – but this is ameliorated somewhat if you do go for one of the large capacity drives. That’s because each drive in the 870 Qvo family comes with a proportionally-sized DRAM cache, which massively speeds up access to recently used data. On the smallest 1TB model, you only get a 1GB cache, but this scales up all the way to an 8GB cache on the 8TB drive. That’s a pretty impressive size – it’s at least the amount of RAM you’d expect to find on a full entry-level PC! – and it means that actually filling that cache is pretty unlikely for normal consumer applications like moving files around or playing games.