Newest SSD's read speeds have reached limit of SATA III?

I've read that even though SATA III is theoretically capable of 600 MiB/s
it's impossible to reach these speeds because of the overhead of
the serial transmission overhead.

Tomshardware seems to think that the newest SSD's have reached
the practical limit of SATA III -- at least for sustained reads.

Are writes for SSD's only slower than reads when cells have to
be erased before they're written?

Basically, the sustained reads are maxed out. Sustained writes sometimes run into controller hitches, sometimes when doing block scrubbing like you said.

I wish drive manufacturers would put more focus on the 4k speeds. After all, most programs are broken up, and scattered in multiple places around the drive. It's got a long ways to go before it hits the SATA III bottleneck


That's why the pcie drives are so much faster, btw. They're not bottle-necked by the sata controller anymore.

We have been at the limit of SATA III for years, ever since the first SandForce drives in the beginning of 2011, which, incidentally, was about the same time Intel first added SATA III support to its chipsets.

EDIT: Also, the SATA limit is not 600 MiB/s, but 600 MB/s.

+1... I mentioned this in your other thread too...

Writes are slower than reads always for all intents and purposes. Whether it has to 'scratch' the data there first before writing or if the cell is ready, its slower.