Sabrent and Phison Are Collaborating to Develop PCIe Gen5 SSD with Speeds Up to 14,000 MB/S

[Zarathustra]

I have a 1TB 970 pro and a 2TB 980 pro in the same system if there was a particular comparison that would be useful

I mean, you could run Crystal disk mark on both and compare the numbers, but I'm guessing that the fact that the 970 Pro is Gen3 will likely mask many of the differences.

In theory the big differences are threfold:

1.) Big long sequential writes that exhaust the cache. On an MLC drive you should see almost constant write speeds across the drive. On a TLC drive you'll be humming along at full speed, but once you exhaust the write cache (usually a combination of RAM as well as cells dynamically acting as SLC or MLC depending on the drive) you should eventually hit a wall after which performance will drop. That wall will likely come sooner the closer the drive is to being full, as then less capacity is available for SLC/MLC write cache.

Personally the only time I ever really run into this is when I am imaging an entire drive. The tail end can be a bit slower. It hasn't really been a huge problem for me in practical use. Usually something else is the limiting factor before the TLC drive I am writing to anyway. I tend to not average higher than ~1.6GB/s for disk image writes either way.

2.) Write endurance. But this you wont find out until way down the line after years of heavy writes. Generally this limitation of TLC has been offset by better optimized write amplification in controllers, and larger drive sizes. it hasnt been a problem for me. At least not yet. That said, I probably wouldn't use a TLC drive as a server cache drive as I would an MLC drive. MLC drives should take a little bit more abuse.

3.) Resistance to corruption. More electrical levels per cell in theory leads to a higher risk of voltage degrading to the point where a bit flips, but I think this has mostly been mitigated through the use of better and more sensitive controllers. That said, an SLC or MLC drive can likely last longer disconnected from power without experiencing corruption than a TLC or QLC drive can, though I'm not convinced this stretches from the realm of theory into the realm of practice. At least not anymore.

TLC has also brought with it some great benefits.

For instance, there is no way we would have seen brand new 2TB MLC drives for $70, or really for any price under $150. They simply could not have made them for that price.