PCIe SSD Faceoff: Samsung XP941 (128GB & 256GB) and OCZ RevoDrive 350 (480GB) Tested

Final Words

Since we are dealing with two fairly different drives, I will split the conclusion into two by beginning with the XP941. The XP941 is still the fastest client SSD and while the 256GB model does not provide the same performance as the 512GB one, it is still faster than any SATA 6Gbps SSD by a hefty margin. The 128GB XP941 is a different story, though. It is not really faster than the 128GB 850 Pro because at such small capacity the performance is mostly NAND limited, except for large sequential read transfers where the SATA 6Gbps interface is the bottleneck. 

The good news is that RamCity has lowered its pricing since May. The XP941 still carries a premium over SATA SSDs, but it is now more competitive in price at less than a dollar per gigabyte. For US-based customers, finding the XP941 in stock can be a bit difficult; Newegg has both the 128GB and 256GB models listed, but they're on backorder; meanwhile the 512GB model is in stock at Amazon, but only at a highly inflated price of $750.

The RevoDrive is a totally different case. The performance is only better in some corner cases where the drive is fed with high queue depth or large transfer data, and in most typical scenarios it is outperformed by SATA 6Gbps SSDs. In the end, the RevoDrive 350 is nothing more than a pre-built 4-drive RAID array, so it is only faster in cases where RAID in general is a benefit (e.g. heavily parallel IO workloads).

Not only is the RevoDrive relatively slow, it is also super expensive. For the price of the 240GB RevoDrive 350, you could get four 128GB 850 Pros with twice the total capacity and higher performance since the 850 Pro is faster than any single SandForce drive. The same goes for higher capacity RevoDrives too -- it is simply way more affordable to buy a bunch of SATA SSDs and build your own RAID array. Even if you do not know how to create a RAID array, I am sure you can find someone to do it for $50, in which case you would still save money and get a faster RAID array with better drives.

All in all, for those who are in the market for a PCIe SSD, the XP941 is the only serious option. It is the fastest client SSD on the market and as long as your motherboard includes boot support for it, it is the best client drive that money can buy at the moment. I am very excited to get my hands on the SM951 (and other native PCIe SSDs) because the XP941 is already great, but when you add PCIe 3.0, NVMe, and V-NAND to the mix it will be one hell of a drive.