As we’ve seen, RAM speed is one of the factors that affect performance, but how much of an impact does it have? You might think that faster RAM will always perform better than slower RAM, but it isn’t always that simple. If you buy faster RAM and your motherboard doesn’t support it well, you might end up with more problems than you bargained for. And sometimes faster RAM can actually slow your computer down! Read on to learn what factors affect your computer’s memory performance and how to pick out RAM that matches your specific needs.
Is the higher frequency better?
Higher frequencies are great because they reduce wait time in between reading/write cycles, but it’s not so simple to say that higher frequency means higher performance overall. The amount of work done by each component is tied to how long it takes for data to be read from and written to storage media. Since most processors are capable of reaching much higher speeds than memory, memory has a lot more work per cycle. That being said, there are a few tricks we can use (or trade-offs we can make) that allow us to utilize faster components without sacrificing system performance.
The differences in latency
It’s easy to get confused by motherboard specifications when they all say things like Dual-channel DDR3, 4 slots, maximum 32GB. This is not always as straightforward as it sounds. Dual-channel memory only refers to memory bandwidth, not latency. For example, there are four channels in total (A1+B1, A2+B2, etc.), and if you plug a pair of DIMMs into every channel that’s theoretically a maximum throughput (memory bandwidth) of 16GBps. If you use two DIMMs per channel (just a pair for A1 and B1) that gives you an effective memory bandwidth of 8GBps.
Why two DIMMs per channel only increase memory bandwidth if you have four DIMMs?
There’s been a lot of debate over whether adding more memory per channel actually increases memory bandwidth. Some articles have shown that using two DIMMs per channel (instead of one) will increase your memory bandwidth, while others have found that it can decrease it. The problem has to do with how fast you run your memory. If you only use one DIMM in each channel, then you’re running it at just half speed (667 MHz instead of 1333 MHz). But if you use two DIMMs in each channel, then you’ll be able to run them both at full speed (1333 MHz), since they’re on separate channels.
Frequency versus latency
This is a matter of personal opinion. In my opinion, yes it is worth paying extra for higher frequency DRAM. It all depends on what you do with your computer, and what applications you use. Certain programs are optimized to take advantage of memory with faster clock speeds, while other programs have no problem using slower memory. Ultimately it boils down to whether or not you really need that extra boost in performance when using certain apps, and how much money you’re willing to spend.
Timings matter A lot
Why go for fast memory when you can get away with slower speed, cheaper models that have plenty of headroom to offer you years more computing performance in your desktop computer? In fact, it’s kind of shocking to find out how much faster some DDR3 and DDR4 modules are than others. Take, for example, Crucial’s BLS4G4D240FSD (8GB) and BLS2K8G4D240FSA (8GB). The latter runs at 1600MHz, while its successor runs only a mere 100MHz higher at 1666MHz. Would a 100-200 MHz boost justify shelling out $75 extra per module?
Is it worth paying extra for higher frequency DRAM?
You may have seen advertisements for 1600 MHz memory. A memory module advertised as 1600 MHz will, in most cases, perform faster than one advertised as 1333 MHz. The frequency of a module refers to how fast it can send data to your CPU; a higher frequency means more performance and more money. However, there are caveats that must be considered before spending extra on higher-frequency modules.