Installing an SSD in your PC, be it a laptop or a desktop, is one of the easiest and most effective ways to boost the machine’s overall performance. The change won't be merely noticeable—it will startle you. Your system will boot more quickly, windows and menus will jump open, and programs and data will load much, much faster.

In case you don’t know what an SSD is, the acronym stands for solid-state drive—that is, solid-state as in no moving parts, and drive as in the fact that an SSD appears as a hard drive to your computer. But instead of storing data on one or more spinning platters, an SSD writes and reads data to and from nonvolatile flash memory. In addition, an SSD contains a controller that's analogous to the memory controller in your PC’s CPU or core-logic chipset.

Many vendors sell SSDs, but the devices are far from equal. Flash memory and controller technology have both advanced so quickly that what was fast last year is now second-class. The drives you might find in the bargain bin will be faster than a consumer-grade mechanical hard drive, but they won't deliver the astounding performance boost you'll be looking for after you read this article.

To get the skinny on state-of-the-art consumer SSDs, we brought seven drives from five vendors into the PCWorld Labs and put them through the wringer. We tested Corsair’s Neutron and Neutron GTX drives; Kingston's HyperX 3K; OCZ's Vertex 4 and Vector drives; Samsung’s 840 Pro; and the SanDisk Extreme. We also retested Intel’s 240GB Series 335 SSD using our new benchmarking procedure (if you're curious, read our original review). Each drive delivers either 240GB or 256GB of storage, which is the current sweet spot in terms of price and performance. Each drive we tested proved to be a solid performer that will offer a significant boost over whatever conventional drive your machine has now. Some drives, however, are definitely faster than others.

If you’d like to upgrade a computer equipped with an older second-generation SATA interface (which maxes out at 3 gigbits per second), note that we also checked out the Apricorn Velocity Solo x2, an add-in card that upgrades any computer with an available PCIe 2.0 x2 slot to the newer SATA 6-gbps standard.

But before we dive into those reviews, here’s a primer on SSDs that will tell you everything you need to know about this technology.

Controller

The memory/interface controller proved to be a major factor in determining each SSD's performance. Three of the drives we tested use a SandForce SF-2281 controller: the Kingston HyperX 3K, the SanDisk Extreme, and the Intel Series 335 (the controller firmware on this drive is tweaked to Intel’s specifications). OCZ’s Vector and Vertex 4 drives both use OCZ's proprietary IndiLinx controllers, namely the Everest 2 in the Vertex 4 and the Barefoot 3 in the Vector. Corsair is blazing a path with its Neutron series drives (the GTX and Neutron) by using Link A Media's LM87800 controller. Samsung's 840 Pro utilizes the company's proprietary MDX controller.

As you'll see in our performance chart, drives with the IndiLinx, Link A Media, and Samsung MDX controllers boasted significantly faster write speeds than the SandForce-based competition. In fact, counterintuitively, each of the five drives using those controllers wrote faster than they read. The SandForce-based drives were all good readers, but their comparatively slower write speeds dragged down their overall scores.

On the next page (scroll down past product-reviews for the link), I'll discuss memory types, interfaces, and how we measured performance.