Samsung's 840 comes in three capacity sizes with six product SKUs. Let's focus on the 500GB today and later look at the 250GB model. We're working on acquiring a 120GB and expect it to arrive before CES.
Rarely do I need to go back and look at the benchmark data to come to terms with the user experience. When we test new architecture, I run the drives in a system for a couple of days. The OCZ Vertex 4 was another drive I had to go back and ask myself is the data presented in the review matched what I felt while using the drive. In both cases the user experience was better than what the benchmarks showed.
Anyone that says all SSDs are the same doesn't own more than one SSD with different architectures or they use them with performance reduction states enabled (C-States, EIST, PCIe Link Management). Little things like high write latency become annoying when you run into slow performance several times when doing daily tasks. Going into this review we expected the 840 to have worse write latency than the 830 we tested, but that wasn't the case even though TLC NAND has higher latency than MLC flash. Samsung managed to beat the issue back with the new controller and programming/firmware.
The read performance from the 500GB 840 is class leading. It sets a new standard for budget SSDs and the lead carries over into enthusiast, prosumer and power user territory. So much of what we do with our computers daily relies on low queue depth read speed and the 840 is a beast in this area.
The write performance is in line with what we expect from a drive designed for the budget category. The only real problem is very good Team SandForce drives with Toggle and synchronous flash have dipped into the budget category. Several companies have tried to make a specific SSD for the budget market, but the low prices of otherwise enthusiast SSDs have been a brick wall to success at low price points.
The Samsung 840 500GB with TLC flash costs $379.99 at Newegg with the basic bundle, a great price point for 512GB of NAND flash. The SanDisk Extreme 480GB costs $314.99 at Newegg at the time of writing and now that SandForce has TRIM working again, well... that closes the door on the 840.
Not all is lost though for the 840. The drive does a really good job in the power tests and delivered solid battery performance in our Lenovo W530. If you need an additional 60 minutes of battery life from your notebook with a typical 500GB, 5,400 RPM mechanical drive, the 840 will give you around 40 minutes more than the Extreme, as long as your notebook is configured like ours.
With SSDs you can pick and choose the specific features you want based on what you're looking to use the drive for. If notebook battery life is what you're after than the 840 is a good choice. If you want the absolute lowest price or the best general use performance, it's not.