ADATA SP900 128GB SSD Review
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Today we’re going to take a look at the new 0-provision LSI SandForce Driven SSD from ADATA, the SP900 128GB. This drive brings with it a few twists that we will be examining to find what effects they have on the drive. The first being the ADATA SP900 is the first or one of the first SandForce drives to have no over-provisioning. Prior to the SP900 drive all SandForce drives came in an over-provisioned configuration, meaning there was less drive space available than actual NAND on the drive. Over-provisioning began with the SandForce 1200 series SSD Processor that launched with 28% over provisioning. For example, the 50GB SandForce controlled drives actually had 64GB of NAND on the PCB with 50GB available to the user prior to formatting. Over provisioned space (OP) or, factory spare area is used for internal drive maintenance. OP was considered necessary to maintain peak drive performance. SandForce soon decided 28% OP was not necessary and, standardized 7% of NAND space for OP. Less OP allowed SandForce drives to be marketed at, for example: 120GB instead of 100GB, making the cost per usable GB lower even though, BOTH the 100GB and the 120GB drives actually have 128GB of NAND on the PCB. 7% OP has held true until today.
We are starting to see 0% OP, which is brought about by an implementation of RAISE (click here for a detailed explanation of what RAISE is) free programming. RAISE free programming now puts LSI SandForce drives in the same category as Marvell drives with the big question being how will this affect performance? I‘m kind of old school myself and usually Over-Provision my drives 25% manually by leaving 25% of the drive unallocated. This has been shown to at the very least dramatically extend the life of the NAND, and is the main reason why enterprise drives have at least 25% OP. However, after seeing endurance testing of SSD’s without OP exceed 1000 Terabytes written and still going strong, it’s pretty clear that the typical user or enthusiast simply cannot wear out NAND for many, many years if ever, even with 0-provisioning. So it’s logical to see the progression to 0% OP, which is where we are at with the SP900.
Twist number two for the ADATA SP900 is ADATA’s use of Asynchronous NAND. Asynchronous NAND is a low cost solution that allows the drive manufacturer to keep costs down, while offering SSDs at a lower cost to the consumer. Asynchronous NAND has an “Achilles Heel” to it though…actually 2 of them. First, Asynchronous NAND can’t read or write highly compressed data nearly as fast as highly compressible data. This becomes magnified when combined with an LSI SandForce SSD processor, which relies on compressing data for maximum speed. Second, Asynchronous NAND is more impacted than other types of NAND. As the drive fills up, the performance drops faster. So, there is a trade-off of lower performance for a lower priced Asynchronous drive.
The final twist to the SP900 is that it comes with 5 series LSI SandForce Firmware. This is both good and, a little annoying at the same time. First the good, 5 series firmware brings a new level of performance as shown by high Vantage scoring and increased read/write performance. The SP900 128GB scores over 85,000 Vantage points when empty. Previous to the 5 series firmware the same drive would score about 78,000 Vantage points. As for the annoying part, TRIM does not function with 5 series firmware. The reason I say it’s annoying and not a complete kick in the nuts is, the lack of TRIM seems to have a minimal impact on the performance of certain drives. The SP900 is one of those drives. The TRIM issue should soon be a moot point because the fix is being worked out now. If the fix keeps the new level of performance and provides proper TRIM functionality then it will be pure bliss. Keep in mind the lack of TRIM is purely a firmware issue and has nothing to do with the drive itself or ADATA.
This review is our fourth review of drives with 5 series LSI SandForce Firmware. As we exposed in 3 previous reviews the TRIM function does not work at all with the current firmware. This had only a minor impact on the 240GB Venus Pro 3. Will the ADATA SP900 120GB drive be as resilient or be more deeply impacted by the lack of TRIM as we saw with the Extreme 480GB? I will be testing in a now familiar order I developed exclusively for 5 Series firmware, which will expose the TRIM problem. Then, I will be running the rest of the benchmarks after the drive is put into a state where TRIM will not recover Vantage scoring so, we can observe the effects of this state on most of the benchmarks. The revised benching/filling order will be as follows:
HD Tune Pro
AIDA access time testing
Vantage fill testing (which will bring the TRIM issue to the surface)
Then the following benchmarks in order and only run once each and in rapid succession:
AS SSD scoring and transfer test
PCMark 7 (this is a new test we will be using from here on out)
I feel this will give the best assessment of the drives performance with without TRIM.