Aftermarket SSD On A MacBook Pro: TRIM Gets Tested

Benchmark SSD: Samsung 840 Pro

Now, in Upgrade And Benchmark Your 2012 MacBook Air's SSD, we used OWC's Aura Pro 6G + Envoy, which employs a proprietary form factor and second-gen SandForce controller. According to OWC, TRIM isn't necessary in that configuration because SandForce's (now LSI's) DuraWrite technology frees up more space for garbage collection to do its thing.

In truth, though, DuraWrite and TRIM are complementary. User data pending deletion is still freed up TRIM. So, although DuraWrite does successfully aid in improving performance and minimizing write amplification, TRIM further improves this. That's why we used the terminal window to manually switch it back on.

A MacBook Pro gives you a more flexibility, since it'll accept a 2.5" SSD. That opens the door up to drives from any number of vendors based on different controller technologies and firmware versions. Samsung's 840 Pro is a good example. It's one of the fastest drives we've tested, and as a result we're using them in all of our test beds. But the 840 Pro doesn't have DuraWrite technology; Samsung doesn't benefit from compressible data, and its controller employs its own garbage collection algorithms. All the more reason to get TRIM up and running, right?

Although the company recently announced its new 840 EVO, which should replace the vanilla 840 soon, the 840 Pro remains its top-end model. As a reminder, the drive center on the company's own S4LN021X01-8030 NZWD1 controller and employs a 6 Gb/s SATA interface. The 840 and 840 EVO both utilize triple-level-cell NAND, which has implications on endurance and performance. But the Pro family leans on familiar MLC flash manufactured at 21 nm.

Samsung 840 Pro Technical Specifications