Did you choose memory? With APU you have to choose so

Thanks to the power of Ryzen and Vega, two groundbreaking architectures, AMD's new generation of APUs made a big entrance with high expectations and performed exceptionally well in all tests. Xiao Bian's friends couldn't wait to save up some money and get their hands on one right away. They were ready to build a small PC that could handle gaming and office tasks. At this point, Xiao Bian, who was busy testing the APU platform, asked his friend: "How are you planning to allocate your memory?" His friend was taken aback. Is that even an issue? To explore the relationship between APU and memory, Xiao Bian selected some 3DMark tests for gaming performance, Fritz Chess for pure computing power, and CineBench R15 for professional graphics applications. The goal was to show how APU works best with different memory configurations.

One-step setup

Since AMD processors have relatively high memory demands, and since APUs integrate the GPU without dedicated VRAM, they must borrow system memory. This puts higher demands on memory bandwidth. Therefore, it goes without saying that high-frequency memory combined with dual-channel configuration is the optimal choice for APUs. Currently, DDR4 3200 is the highest frequency memory available on the market. Xiao Bian naturally went for DDR4 3200 in a dual-channel setup to test its performance.

The test results showed that using dual-channel high-frequency memory provided the best performance, significantly boosting both the APU's integrated graphics and overall system memory performance. In fact, the results even surpassed those of the GT1030, which was quite impressive. So, if budget allows, this combination is definitely the most ideal choice.

Old memory still has value

In addition to using the latest and most expensive DDR4 3200, there are still older memories like DDR4 2133 or DDR4 2400 that people might want to reuse on the APU platform. What would the results look like in that case? According to the tests, even with dual-channel DDR4 2400, the theoretical bandwidth is only about 75% of that of dual-channel DDR4 3200. The difference is significant, and it does impact performance. Although dual-channel mode was used, the performance of DDR4 2400×2 was still far behind the best solution. In fact, it was even lower than single-channel DDR4 3200. Surprising? Maybe not. In terms of graphics performance, the 3DMark score was equivalent to 85–90% of the dual-channel DDR4 3200, while the professional graphics performance was only around 80%.

Clearly, high-frequency memory has a major impact on APUs. There's a noticeable gap between the performance of DDR4 2400 dual-channel and DDR4 3200. However, it's better than nothing, and it's always better than running in single-channel mode.

Future potential

Now that memory prices are still quite high, buying two DDR4 3200 modules may stretch your budget. Xiao Bian suggests that you can opt for a single high-frequency module for now and upgrade to dual-channel later when prices drop. This approach will allow you to make the most of your APU’s performance, although it will sacrifice some performance initially. From the test results, the CPU unit of the next-gen APU isn’t very sensitive to memory bandwidth, but it's highly dependent on memory frequency. All CPU-related test scores were close to the dual-channel setup, with single-channel reaching up to 97% of dual-channel performance. However, in graphics performance tests, the lack of bandwidth became apparent. 3DMark and professional graphics scores were only 65% and 73% of the dual-channel setup, respectively.

This clearly shows that without spending extra, the impact of a single memory stick on the integrated graphics is quite large. This configuration is suitable for users who plan to upgrade soon or aren't heavily into gaming.

 

After seeing Xiao Bian's test, his friend had a clearer idea of how to make the most of his limited budget. He opened an e-commerce site and said, “Go ahead, do it!”