Toshiba's Q Series Pro is a drive that you may not have heard of - yet. Toshiba launched this drive a couple of months back, and we've finally got our hands on a pair. Toshiba is one of the largest NAND flash manufacturers on the planet; in fact, most of the top performing drives we're seeing these days are equipped with 19nm Toshiba flash in BGA packages.
When you make the flash, you bin the flash, and when you bin the flash, you save the best for your own products, and sell the rest. When you have access to the best performing flash, you can make the best performing SSD's. Toshiba is in this enviable position. Toshiba can make SSD's that feature the very best binned flash, and still produce those drives for less cost than any fabless SSD manufacturer.
It's all about the flash. NAND accounts for 85% of the cost of manufacturing an SSD. While controllers are important, aren't responsible for all of the performance of the SSD. The NAND plays a very vital part. NAND is like the blood in a heart, while the controller is like the heart itself. If the blood is bad, it doesn't matter how good the heart works, the outcome will still be unfavorable. Typically, LBA mapping tables are kept in DRAM to speed up performance of the SSD's internal functions. The Q Series Pro doesn't use DRAM, likely because the NAND is fast enough to provide the performance on its own. This is the first time I've seen a retail SSD with a DRAM-less design, other than SandForce.
A DRAM-less design is where Toshiba is "breaking all the rules," so to speak. The thing about a DRAM-less design is that without DRAM, synthetic benches don't get smoothed out, and write performance seems choppy and inconsistent. However, this choppy performance doesn't really manifest itself until we load the drive up with data.
The Q Series Pro's performance with data on the drive is a perfect example of why FOB (Fresh out of Box) testing (testing without data on the drive) can never accurately depict a drive's actual performance. I mention this because some reviews I've read from sites that review utilizing FOB testing have totally missed the mark when they reviewed the Q Series Pro. If you don't test with data on the drive, then you won't see the choppy write performance that manifests itself on certain synthetic based tests like ATTO, CDM, and Anvil's. More importantly though: FOB testing will not show you that the Q series Pro is one of the fastest SSD's ever made. If you just FOB test, you would think the Q series Pro is just an average, or below average SSD; you wouldn't even know what you had in your hand.
We try our best to mimic a consumer implementation by testing our drive/array as our OS volume, or "C" drive, and filling the drive/array to 75% of its capacity with random 4K data. As we work our way through today's review, we will be able to show you firsthand why testing a drive with data on it is so important. The Q Series Pro has even managed to contradict some of our own preconceived notions about an SSD's performance indicators.