OWC SSDs are engineered to be the.LTR: Gen. At the bottom of the window is a box labelled Options.Aura Pro 6G SSD for MacBook Air 2012 is designed and built with premium tier-1 NAND flash and backed by a 5-year warranty. Under where it says Partition Layout, select 1 Partition.The SATA standard’s been in use for many years and is still the most prevalent interface for connecting internal storage drives.The SATA standard has now undergone three major revisions, resulting in connectors that are identical in appearance (hurray for backwards compatibility), but with bandwidth doubling each time. Luckily, advances in host interfaces invariably stay ahead of the pace of drive technologies, always allowing room to push speeds a bit farther.SATA (Serial Advanced Technology Attachment) refers to the technology standard for connecting hard drives, solid state drive, and optical drives to the computer’s motherboard. If you are, it’s time to get up to speed!Ever faster drive technology, brought about by faster spinning disks, increased cache, advances in controller architecture, and a host of other factors keeps pushing the host interface to become the bottleneck for read and write speeds. If you’re into vintage computers and you think patience is a virtue that can only be honed by waiting for programs to respond, maybe you’re still rocking a drive with a PATA interface.It’s no wonder that manufacturers moved towards PCIe technology for their bandwidth hungry SSDs. In short, SATA just wasn’t made for solid state drives.Peripheral Component Interconnect Express (PCIe) is a computer bus standard with incredibly high bandwidth potential, and is the fastest bus option that most computers have available. And even if you’re using a SATA III interface, you’re still probably limiting your SSD. But as it applies to SSDs, if you’re not using a SATA III connection, it’s safe to assume you’re limiting the potential of your drive.That 20% overhead eats into the potential bandwidth of an interface, resulting real world bandwidth that’s 20% lower.PCIe 3.0 introduced the much more efficient 128b/130b encoding, resulting in only only ~1.5% overhead to eat into the potential bandwidth.Advanced Host Controller Interface (AHCI) was originally created when storage devices still used spinning magnetic disks to store data. In other words, 2 of the 10 bits are just overhead necessary to transmit the rest of the data. PCIe 1.0 and 2.0 both use 8b/10b encoding to transmit data (the same as SATA), meaning that for every 8 bits of data sent, the data is sent via a 10 bit line code. Most PCIe SSDs will have either 2, or more recently, 4 channels of throughput.In 2011 the PCIe 3.0 revision was released, and finally brings more to the table than just the ability to add additional channels. Those speeds may sound a bit slower than SATA III, but PCIe has the advantage of utilizing multiple channels of throughput to accommodate the needs of the connected peripheral.Two channels of throughput (~1GB/s) not enough for you? Double the number of channels to four and you’ll realize double the data transfer rates, if the connected device can make use of it that is. PCIe bandwidth can be scaled up to 16 and even 32 lanes for a single device, but that’s uncommon in SSDs and primarily reserved for devices like graphics cards which have larger data transfer requirements. PCIe 2.0 (which is likely to be the most common PCIe revision found inside in-use computers) maxes out at ~500MB/s with a single channel of throughput.
Ssd Mid 2012 Full Potential ThroughputAnd unlike M.2 pin arrangements, Apple’s connectors were never given distinguishing names, so from this point on I’ll just refer to the connectors by their pin arrangements as described in the image below. With the 2010 MacBook Air, Apple began a new trend of developing proprietary connectors and form factors that eventually pervaded the entire Apple lineup and ushered in an era of drives that, while easily replaceable, were not so easy to find.Many people incorrectly assume the connectors are one of the M.2 variants found in many PCs, but to date, Apple has still never used a standard M.2 connector. By the time the PCIe 3.0 revision came out, NVMe became essential to reach the full potential throughput of the drives.When Apple released their first “blade” solid state drive in the Late 2010 release of the MacBook Air, they still used established mSATA interface technology, but ditched the traditional SATA and mSATA form factors found in most laptops at that time, instead opting for a custom connector that’s never been used by another manufacturer before or since. NVMe becomes especially important with PCIe SSDs, where AHCI starts to bottleneck the speeds. NVMe was created specifically to work with SSDs, reducing the latency and allowing for larger amounts of data to be transferred at a single time, making better use of modern multi-core processors. AHCI was versatile enough to work with SSDs while SSDs were still in their infancy, but it’s been a hindrance to transfer rates for a few years now.Enter NVMe, or Non-Volatile Memory Express. Both drives performed up to Apple’s advertised specs, mind you, but MacBook Air customers were subject to an SSD lottery, with Samsung drives performing reads and writes at ~1.5x-2.0x the speed of their Toshiba counterparts. This “Generation 1” drive utilized a proprietary 6+12 pin connector, but still used an mSATA III interface limited to 6Gb/s the same limitation as the other product lines released during this period.Both Samsung and Toshiba manufactured Apple’s Generation 1 SSDs, but rather notoriously, the Toshiba drives performed significantly worse than their Samsung counterparts. Rather than use a 2.5″ SATA SSD as seen in the rest of Apple’s product lines, or even the 1.8″ SSD found in the original MacBook Air, Apple switched to an even thinner, custom drive. Visual studio for mac vs visual studio codeThe operating system displays the two drives as a single drive to the user, but behind the scenes optimizes file storage so that files requiring more frequent access and files that see the most benefits from quick read times are stored on the SSD, while the majority of the files are stored on the HDD. Apple’s Fusion Drive pairs a larger capacity traditional hard drive with a smaller capacity solid state drive, offering much of the performance benefits of an SSD, but in a more cost-effective package. 2A SSDs used by these MacBook Pro laptops were offered in 128GB, 256GB, 512GB, and 768GB capacities, and manufactured again by Samsung, but also by SanDisk.Both the 13″ and 15″ MacBook Pro laptops use the same drives, and either MBP can have any of the four SSD capacities installed.The Late 2012 and Early 2013 iMacs had a rather different arrangement, with a traditional 3.5″ SATA III HDD standard, but the Late 2012 release also unveiled the Fusion Drive.
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