It's a foregone conclusion that SSDs are must-haves in performance-oriented PCs, but our testing reveals that solid-state drives are reasonable upgrades in older mainstream machines, too. We build three old boxes to gauge the impact of an SSD on each.

The solid-state drive industry is currently shifting from the 3 Gb/s to the 6 Gb/s SATA interface, increasing potential throughput from 250+ MB/s to more than 500 MB/s. Enthusiasts currently hamstrung by slow storage performance can definitely appreciate the higher ceiling, particularly in new builds with cutting-edge processors and powerful graphics configurations.

However, we also find ourselves wondering if an SSD makes sense as an upgrade in an older system with components that might not be as fresh any more. It turns out that yes, solid-state technology does have a place alongside previous-generation hardware. It doesn't take a Nehalem- or Sandy Bridge-class configuration to let flash-based media stretch its legs after all.

This article looks at what happens when you replace an existing hard drive with a solid-state drive. We built a few systems that represent PC hardware from 2005, 2006, 2008, and 2010, and then upgraded each of them using an SSD.

Processor, graphics card, and motherboard vendors might not like this revelation, but here it is anyway. If you're not an enthusiast with specific performance requirements, it's not necessary to buy new components every time AMD or Intel launches a platform. If you're just browsing the Internet, using social media, watching video, communicating over Skype, or word processing, a five-year-old Core 2 Duo still probably feels like a snappy-enough system. Granted, gaming, workstation apps, and transcoding workloads are all great reasons to invest in modern components. But entry-level, mainstream Windows-based boxes simply don't need any more muscle than that.

Once you do feel an urge to upgrade, the question becomes: where to start? Should you drop in a new processor? Many folks like to think that simply adding more RAM is the cure-all; will dropping in additional modules help? Would a new graphics card address the situations where you notice slow-down? Or how about a larger hard drive because you're simply running out of space? There are plenty of ways to spend money trying to beef up the speed or capacity of an older machine.

But almost nobody considers adding an SSD. After all, an SSD is hardly effective for addressing capacity issues. And SSDs generally fall below all of those other parts when power users think about the pieces that'd help improve performance.

Before you even try dropping an SSD into an old box, though, consider a couple of caveats first. We're neither concerned with the model of drive you use, nor the price at which you buy it. Practically, even value-oriented SSDs are considered relevant when it comes to upgrading aging hardware. However, we do want to mention that it is important to use a SATA controller with AHCI support because it's necessary to support the TRIM command. Every SSD can be operated without TRIM, but at the risk of decreased performance after intensive use. As more general guidance, there is a minimum amount of processing power and memory you'll want before an SSD makes sense. Own a decent dual-core CPU and at least a couple gigs of memory. Otherwise, you're probably on a trajectory for a full system revamp, and not just a single-component upgrade.