When OCZ released the Vertex 4 in April, it brought us excepionally great write performance. Based on OCZ's Everest 2 controller (Marvell IP with custom firmware), the Vertex 4 began OCZ's transition away from SandForce for its high-end drives. However, as we noted in our review, sequential read performance at low queue depths needed work in the launch firmware.

Fortunately, OCZ was well aware of the issue and it only took them a bit over a month to come up with a firmware update to address low queue depth sequential read performance. We updated our Vertex 4s (including the 128GB model that was missing in our initial review) to the new 1.4 firmware and ran them through our suite. By the time we finished running our 1.4 tests, OCZ had already released an even faster 1.5 firmware, so we decided to kill two birds with one stone and combine the two updates into one article.

The 1.4 Firmware

With the latest versions of OCZ's Toolbox, you can now update your drive's firmware even if you have Intel's RST drivers installed. The toolbox actually downloads the drive's firmware from OCZ's servers before updating your drive, so you'll need to have an active internet connection. I have noticed that older RST drivers may trigger in a firmware file not found error during the update process, but the absolute latest RST works as well as Windows 7's standard AHCI drivers. The toolbox update is only possible on secondary drives, not the drive that Windows booted from.

Note: Upgrading to 1.4 firmware is destructive, meaning that your SSD will be erased in the process. Thus it's absolutely necessary to make a backup of your data before upgrading, unless you are fine with losing the data in your SSD.

Increased read performance at low queue depths

Improved sequential write performance for 128GB and 256GB models

Increased performance under specific workloads of mixed reads and writes

Improved host compatibility with dated/uncommon BIOS revisions

Improved stability when resuming from S3/S4 on older generation motherboards

Increased read performance on small file sizes (lower than 4K)

The release notes are promising. Read performance at low queue depths is exactly what needed fixing and 1.4 claims to address this directly. OCZ also published an updated performance table, which is below:

OCZ Vertex 4 with 1.4 Firmware Specifications Capacity 64GB 128GB 256GB 512GB Sequential Read 460MB/s 535MB/s -> 550MB/s 535MB/s -> 550MB/s 535MB/s -> 550MB/s Sequential Write 220MB/s 200MB/s -> 420MB/s 380MB/s -> 465MB/s 475MB/s 4K Random Read 70K IOPS 90K IOPS 90K IOPS 95K IOPS 4K Random Write 50K IOPS 85K IOPS 85K IOPS 85K IOPS The 64GB model was introduced along with the 1.4 firmware and it will be shipping with the new firmware, hence only one set of performance figures. As for other capacities, sequential read performance is up by 15MB/s. That's not a significant increase, although it should be kept in mind that we are very close to the limits of 6Gbps SATA already. However, this data does not tell whether sequential read performance at low queue depths is what it should be. As we discovered in our review, increasing the queue depth lead to better results. Sequential write performance, on the other hand, is significantly improved in 128GB and 256GB models. The 128GB model had a fairly poor write performance at 200MB/s before the update, but the 1.4 firmware brings that to 420MB/s. That's over 100% increase, which is fairly abnormal but welcome for sure. The 256GB model is also getting a 85MB/s (~22%) boost in sequential write performance. Random read and write speeds remain unchanged for all models.

The 1.5 Firmware

Note: The 1.5 upgrade is destructive if upgrading from 1.4 RC or older. However, if upgrading from final version of 1.4 firmware, the upgrade is not destructive. We still recommend having an up-to-date backup of your data because something may go wrong and result in a data loss.

Improved sequential file transfer performance for 128GB, 256GB and 512GB models

Optimized idle garbage collection algorithms to extend the benefits of performance

mode by enabling the feature across a greater percentage of the drive

mode by enabling the feature across a greater percentage of the drive Improved HBA / RAID card compatibility

Further improved compatibility with desktop and mobile ATA security features

Corrected a corner case issue where the ‘Remaining Life’ SMART attribute could be reported incorrectly

OCZ Vertex 4 with Firmware 1.5 Specifications Capacity 128GB 256GB 512GB Sequential Read 550MB/s -> 560MB/s 550MB/s -> 560MB/s 550MB/s -> 560MB/s Sequential Write 420MB/s -> 430MB/s 465MB/s -> 510MB/s 475MB/s -> 510MB/s

The 1.5 firmware provides more incremental improvements compared to the 1.4 firmware. Sequential read speed is up by 10MB/s (~2%) and sequential write speeds are up by 2-10% depending on the capacity. Apparently, the 1.5 firmware does not provide any performance gains for the 64GB model. The other remarkable change in 1.5 firmware is enhanced garbage collection. This update actually relates to a unique performance mode OCZ introduced with the 1.4 firmware.

The Performance Mode

With the 1.4 firmware OCZ introduced a two operating mode structure for most capacities of the Vertex 4. As long as less than 50% of the drive is in use, the Vertex 4 will operate in a performance mode - delivering better sequential performance. Once you hit the 50% mark, the drive switches to its standard performance mode (similar to the max performance pre-1.4 firmware).

This mode switching is mostly transparent to the end user with one exception. When you cross the 50% threshold, the Vertex 4 has to reorganize all pages on the drive. During this reorganization performance is impacted. The entire process should only take a matter of minutes, and it only happens once, but it's worth keeping in mind.

You may remember Intel did something similar (on the fly internal data re-organization) after the first X25-M firmware update, however that process took much longer.

This isn't the only performance trick OCZ has up its sleeve, but it is something that is enabled by the fact that OCZ finally has full, low-level control over the Vertex 4's firmware.