Who could argue with faster components? It's no surprise that fast memory floods the pages of Newegg and the shelves of Micro Center, with eager builders trying to squeeze out every edge when it comes to performance. But you probably don't need to spend up for a speedy kit of memory, and if you believe some old myths about memory speed, you'll end up spending more than you need to.

5 You don't need to buy fast memory

It exists for a reason

There's some traditional wisdom in the PC building community that high-speed memory is, generally, a waste of money. There's a lot of truth to that. In most generations, there's a sweet spot for memory that quickly dominates builds. In the previous generation it was DDR4-3200, and now, it's DDR5-6000. For the vast majority of builds, you can stick around this sweet spot, and you won't have any issues. Beyond this point, you either see a minuscule improvement in performance or no improvement at all.

However, there are some situations where fast memory is a major asset. For instance, APUs scale remarkably well with fast memory, as your RAM is shared across both the CPU and the integrated GPU. Some architectures prefer fast memory, as well. Intel's recent Arrow Lake chips like the Core Ultra 9 285K favor oddly fast memory, for example.

In most cases, you don't need to buy fast memory, but it exists for a reason. Instead of writing off memory speed wholesale, it's worth looking into the particular CPU you have to see if faster memory can provide any performance benefit.

4 Faster memory results in better performance

Past a certain point, you're just wasting money

I'm undermining the first point with this second one, but I'm doing it for a good reason. Some CPUs and platforms see good scaling with faster memory, but it's still true that the vast majority of builds are fine with the "sweet spot" of that generation. The tricky part about picking out memory based on speed, though, is that a kit that appears faster on paper can actually be slower in practice.

Speed, or frequency, is only one metric that determines RAM speed. There are a string of timings that determine the total latency of the memory, which can make seemingly faster kits slower in practice. Let me provide an example. DDR5-6000 kits generally come with a CAS latency (CL) of 36, while a slightly faster kit like DDR5-6400 may come with CL40. In this case, the "slower" kit actually has lower overall latency than the "faster" one. It's counterintuitive, but in this case, spending more for the DDR5-6400 kit won't net you any better performance. It may actually hamper your performance (though only marginally).

3 You can buy any high-speed kit of memory

Compatibility doesn't matter; until it does

CPUs have a memory controller that's only rated to support up to a certain speed. For instance, 13th-gen Intel chips only technically support up to DDR5-5600. The controller always maintains a very conservative speed that's in-line with JEDEC spec; the ones that define DDR standards. You're able to go past the capabilities of the controller with an overclocked kit, which is why DDR5-6000 should work just fine with a 13th-gen CPU given that you have XMP turned on.

Don't throw the baby out with the bathwater, though. Although you can safely go above the memory controller's capabilities, that doesn't mean you'll be free of issues. Every motherboard has a list of certified DIMMs that have been validated for that platform, and it's a good idea to shop off this list if you can. There's a good chance that you'll be fine even if your specific kit isn't listed, given that other kits with the same speed and timings have been validated. But there's always a chance.

Still, if you have the foresight to shop for a kit off the validated list, I recommend doing so. You probably won't run into issues with an unvalidated kit, but I've encountered a handful of situations where a specific kit of memory didn't play nice with a motherboard, and that's a difficult problem to troubleshoot.

2 Faster RAM improves gaming performance

Not a myth, but a misconception

This one is tricky because it's not a myth. Faster memory can improve your gaming performance, and depending on the CPU you're looking at, it can represent a decent uplift. Going from JEDEC stock speeds to something like DDR5-6000 can represent around a 10% jump at 1080p on recent AMD chips, for example. There's an awful lot of context lacking from a claim like that, however.

I like to think of RAM as an extension of the CPU, and that holds up well when looking at gaming performance. Especially more recently, we've seen an increase in the amount of cache included on CPUs, not only in the form of X3D chips like the Ryzen 7 9800X3D, but also in the main stack on CPUs like the Core Ultra 9 285K. Generally, the more cache available to the CPU, the less of a benefit you'll see from faster RAM.

CPU cache is significantly faster than RAM. It's akin to comparing RAM to your SSD when it comes to the speed difference, and if your CPU already has a lot of cache, a little bump in memory speed isn't going to do a ton for your gaming performance.

1 RAM speed is measured in MHz

It's not, despite what the packaging says

Undoubtedly, the biggest myth that persists with RAM is that the speed is measured in MHz. Outside of being pedantic, understanding the proper metrics for memory speed can have practical implications if you're not careful. Decades ago, RAM speed was measured in MHz. That's when we had SDR, or single data rate, memory. There was one signal per clock cycle, so you could accurately measure the speed of the memory based on frequency.

That's no longer the case with DDR, or double data rate, memory, where there are two signals per clock cycle. The vast majority of memory brands still advertise speeds in MHz, but the more accurate measurement is MT/s, or megatransfers per second. That number comes as a result of taking the clock speed and multiplying it by two. You get two signals per clock cycle, after all, so it doesn't make sure to have a measurement based on single clock cycles.

And, in order to get the full speed of DDR memory, you need at least two channels. If you're buying a kit of two or more DIMMs and putting them in your PC, you don't have much to worry about. When you're shopping for an individual stick, though, be careful. The advertised speed will be slower if you only use a single DIMM — half as much, in fact.