The Samsung 840 Pro performed very well in my testing; it's among the fastest of all the 7mm SSDs I've reviewed. It's not the fastest, however; in fact, it was slower than its predecessor, the 830 series, in a few tests. As with the 830 series, I tested the new drive with overprovisioning off.
The new drive indeed helped the test machine boot up and shut down very fast, taking just less than 10 seconds and about 5 seconds, respectively. There was no delay when the computer resumed from sleep mode. All applications I tried opened noticeably faster. Since most SSDs help significantly boost overall performance anyway, it's very hard to quantify the difference between different SSDs, but I could really see the benefit of the Samsung 840 Pro over many other SSDs I've reviewed.
Again, most users will not see much difference unless they're upgrading from a hard drive to an SSD, but if that SSD is the 840 Pro, the improvement will be absolutely great.
The 840 Pro is also designed for those who have already used an SSD. In addition to the performance bump, it also offers better battery life. I tried it with a MacBook Pro in an anecdotal test and the battery life, when using the Samsung 840 Pro, was about 25 minutes longer when compared with when the computer was used with the stock SSD.
In the data copy test, which is generally not the strength of SSDs, the 840 Pro nonetheless did very well at 257MBps when it was used as a secondary drive. When used as the main drive that hosted the operating system and performed both writing and reading at the same time it now scored 168MBps. Both of these numbers were among the top three on the charts but were still slower than those of the 830 series.
(Shorter bars indicate better performance)
(Longer bars indicate better performance)
|As secondary drive||As OS drive|
With very fast performance and very low power consumption, the new Samsung 840 Pro makes a great investment for those who can afford it.