Not that long ago, it seemed like the most difficult choice when building a system with an Intel motherboard was choosing between memory kits with high-end speed or high-end capacity. With the rising cost of memory and storage, many builders are instead wondering if they can get away with industry standard “green” DIMMs, a single-DIMM setup, or even a mismatched kit — all options that they might not ordinarily consider. While some PC DIY enthusiasts are opting to put off a memory upgrade, focusing on other parts of their system instead, students, content creators, and home office users can’t always play the waiting game due to the need for higher capacity or faster DDR5 DIMMs. Video editing and LLM training, among other PC uses, can easily overwhelm and slow down a PC with insufficient memory.
The good news is that you do have an alternative. Consider purchasing industry standard DIMMs — sometimes called green DIMMs — at a lower price and use ASUS AEMP II / III to bump your performance. With the latest 3002 and 3103 UEFI BIOS updates, ASUS Intel Z890 and B860 boards can more easily mix and match memory – including industry standard profile memory without heatsinks – to maximize performance and capacity through ASUS AEMP II and AEMP III technologies. You can also adjust modules separately with Intel XMP profiles through our ASUS DIMM Fit and DIMM Fit Pro technologies.
Brief note: As you’re making a decision about whether to overclock your memory, you should also factor in your product warranty. It’s possible, but not necessarily a given, that overclocking a component will void your warranty, especially if you push the settings so far that you cause physical damage to the hardware.
Memory profiles 101
By now, most PC users are familiar with the process of using memory with an Intel XMP profile. You probably already take this into account when purchasing new memory by ensuring the memory lists Intel XMP or AMD EXPO compatibility, depending on the motherboard you plan to buy.
As a brief overview, Intel XMP (Extreme Memory Profile)-certified memory kits include a profile with preset combinations of speed, timing, and voltage tested by the memory manufacturer for stability. Enabling the profile usually takes seconds in the BIOS and immediately improves the performance of your system. If you want to learn more about Intel XMP, click here.
But what if your memory doesn’t support XMP? Many memory manufacturers also offer industry standard memory modules designed for stability, rather than cutting-edge performance. AEMP was literally designed for these circumstances.
What is AEMP and why should I use it?
ASUS Enhanced Memory Profile (“AEMP”) technology debuted on our ASUS Intel Z690 motherboards in 2021. More recently, we announced that improvements to AEMP II and III enabled support for 4-DIMM configurations up to 256GB. To explain what AEMP does, we first need to discuss why it only works with industry standard memory.
Unlike performance memory that might support an XMP Profile, JEDEC industry standard memory modules adhere to industry standard speeds, timings, and voltages. These standards are strict, because these DIMMs typically do not have a heatsink, and they are designed with compatibility and stability in mind. Thanks to our extensive partnerships with memory manufacturers and motherboard design philosophy, AEMP provides additional performance and value for these kinds of modules, as Kingston notes in this overview.
Although Intel XMP is configured in your UEFI BIOS simply by reading and applying a profile embedded on your memory, AEMP II and AEMP III look at more than just the JEDEC profiles on the memory.
When you select AEMP II or AEMP III in your UEFI BIOS, the motherboard begins a comprehensive tuning process using preloaded memory profiles designed by our engineers, your DIMMs’ JEDEC profiles, your CPU, and your motherboard’s memory overhead. The tuning process runs through multiple memory specs and voltages to determine the optimal level of performance and stability. This process typically takes less than 5 minutes.
Minimum requirements to use ASUS AEMP
| Series | DIMM FIT | DIMM Fit Pro | AEMP | AEMP II | AEMP III |
|---|---|---|---|---|---|
| Intel Z890 | V | V | X | V | V |
| Intel B860 | V | V | X | V | V |
| Intel H810 | V | V | X | X | X |
| Intel B760 | X | X | X | V | X |
| AMD X870E AMD X870 | V* | V* | V | X | X |
| AMD B850 AMD B840 | X** | X** | V | X | X |
| AMD B650E AMD B650 | X | X | V | X | X |
| AMD B550 | X | X | X | X | X |
*Only ASUS ROG, ROG Strix, TUF Gaming, and ProArt X870E/X870 motherboards
**The ROG Strix B850-E Gaming WiFi is currently the only ASUS AMD B850/B840 motherboard that supports DIMM Fit and DIMM Fit Pro
How to use AEMP on your ASUS Z890 / B860 motherboard
Some basic requirements:
- Your memory must be JEDEC industry standard memory (i.e. does not have an Intel XMP or AMD EXPO profile and probably doesn’t have a heatsink)
- Your DDR5 memory is either U-DIMM or CU-DIMM, but not mixed
- Your DDR5 memory is either single-rank or dual-rank, but not mixed
If you aren’t sure about the specs of your memory, you can use the ASUS SPD Information Tool in your ASUS motherboard BIOS. To get there, go into the Tool menu and select “ASUS SPD Information.” In this screen, you can locate the brand, part number, serial number, JEDEC information, Density per Die, module organization, PMIC, and type of DDR5 – among other information. You can determine if the memory is U-DIMM / CU-DIMM by checking the “Type” and the rank by checking the “Module Organization”, as outlined in the image below.
Mixed-use configurations now supported with UEFI BIOS 3002 and 3103
JEDEC industry standard memory modules come in a variety of speeds, capacity, timings and voltages, but they are closely tuned to run at their specs and remain within normal operating temperatures. Even across different brands and models, this gives our board engineers a lot of room to test and validate using these kinds of memory separately and together due to their similar behavior and performance.
To illustrate the flexibility of AEMP, we took four different sticks of memory across 3 brands, 4 different memory capacities, 2 different speeds and configured them in an ROG Maximus Z890 Extreme via ASUS AEMP II. We tested them with the Intel Core Ultra 7 265K, using the latest BIOS updates:
- DIMM_A1: Samsung 8G 4800MHz – M323R1GB4BB0-CQKOD
- DIMM_A2: SK Hynix 12G 5600MHz – HMCGG6MGBUB213N
- DIMM_B1: Lexar (Micron) 16G 5600MHz – LD5U16G56C46ST
- DIMM_B2: SK Hynix 24G 5600MHz – HMCGJ8MGBUB252N
We start by booting into the UEFI BIOS, go into the Extreme Tweaker menu, and locate the AI Overclock Tuner setting. If the memory is supported, the appropriate AEMP option will become available. Within this menu, you can select AEMP II (or III if using CU-DIMMs) to start the profile process:
Once you select AEMP II, it will analyze your configuration based on the motherboard, CPU, and DRAM characteristics to determine the optimal speed, timings, and voltages. This process typically takes around 5 minutes to complete.
Once the tuning is complete, Save & Reset to apply the changes. You can see the updated profile on the Save Changes & Reset popup screen. In this image, you can see that the DRAM frequency was tuned to 5200 MHz, which is a slight overclock from the previous 4800MHz that was previously selected by the board. CAS Latency was lowered from an average of CL48 to CL36.
After rebooting, you can find the updated memory information on the main page of the BIOS:
To further confirm stability, we then put it through stress testing with MemTestPro:
From the images taken on the desktop, you can compare the original JEDEC specs to the AEMP II-tuned specs to see the improvements. This shows how you can use a variety of JEDEC industry standard memory modules to work together without having to spend time attempting to configure them yourself. More to the point, spending only a handful of minutes in the BIOS improved the speed and timings without sacrificing stability. A small overclock may not seem like a lot, but it can provide a noticeable impact on gaming, projects that run for several hours or days, and even your regular everyday usage.
ASUS DIMM Fit and DIMM Fit Pro tune DIMMs with Intel XMP profiles for higher performance and stability
We’ve covered DIMM Fit and DIMM Fit Pro in detail in a previous post, but the tools have considerable potential for helping you find stability with your memory kit, even the types that we’ve been discussing here. But before we dive into DIMM Fit and DIMM Fit Pro, it’s helpful to first understand what makes DIMMs with Intel XMP profiles different than the industry standard memory we covered above.
DIMMs with Intel XMP profiles are tuned by memory manufacturer engineers above JEDEC specs, but within rigid standards to be supported on Intel motherboards. These DIMMS will generally have better components like PCBs, controllers, and memory ICs – not to mention thicker heatsinks to handle higher heat output – in the pursuit of faster speeds, lower latencies, and reduced cross-talk.
With higher performance ceilings, improved design for overclocking, and more robust PMICs, it makes perfect sense that a different tool is needed to take advantage of kits designed for Intel XMP profiles. This is why DIMM Fit and DIMM Fit Pro exist. While most Intel motherboards can utilize Intel XMP profiles, only ASUS motherboards provide DIMM Fit and DIMM Fit Pro tuning options.
How to use ASUS DIMM Fit and DIMM Fit Pro to improve performance and stability
The main difference between ASUS AEMP and DIMM Fit technologies is that AEMP tunes memory with minimal to no tuning options, while DIMM Fit and DIMM Fit Pro are replete with options to give the user control over their memory. A second difference is that AEMP typically takes only a few minutes, while DIMM Fit and DIMM Fit Pro may take several hours and will reboot many times. While that is a significant investment of time, the payoff can be quite valuable. Here are some of the potential benefits of DIMM Fit technologies:
- Want to push for higher memory speeds? DIMM Fit can help you find that additional bump in stability that turns an almost-there overclock into a reliable profile.
- Having difficulty with crashes after enabling your Intel XMP profile? DIMM Fit can help you figure out small adjustments to achieve stability, and then push beyond.
- Do you dislike using “AI-type” overclocking utilities because you don’t have input in how it works? DIMM Fit Pro is designed to give the user more input to prioritize performance, stability, and more.
The difference between DIMM Fit and DIMM Fit Pro is small, but significant. Both function the same way, but DIMM Fit Pro gives users a lot more control over the utility, including how the utility sets its priority for the final result.
To get started, go into your ASUS motherboard BIOS, go into the AI Tweaker menu, select DRAM Timing Control, and locate the DIMM Fit options within the menu. From here, you can set margins for different specs and behavior by the DIMM Fit utility and let the motherboard take some of the stress out of memory tuning.
Once you’re ready, select a profile option and the process will begin. As noted above, the process may take several hours, during which the board will reboot many times. Once it is complete, it will save the DIMM Fit profile, which you can later restore. This way, you can configure multiple profiles suited for tasks like gaming, or benchmarking.
ASUS Intel Z890 and B860 motherboards help memory go further
Sometimes, even the most useful BIOS features don’t get a lot of attention. Prior to the memory shortage, some of our memory-specific features flew under the radar simply because memory was relatively affordable, and Intel XMP profiles offered “good enough” performance without much fuss or time investment. But now that the memory market has shifted, it’s worth taking the time to reassess the value of some of these tools that have been available for years.
ASUS Intel Z890 and B860 motherboards are designed to give you the most value across the total experience of ownership, including features, accessories, software, and more. ASUS AEMP and DIMM Fit technologies are included in this package, as they give you additional ways to make use of memory you might have laying around, more choices to purchase memory you previously deemed insufficient, or confidence to overclock the memory you have to achieve higher performance.
Through these features, you might be able to use industry standard memory modules for your new build or upgrade, all while spending less money than you might have otherwise and still getting top performance. That’s what we call a win-win.
Frequently asked questions
Q. Is AEMP available with ASUS AMD motherboards?
A. Our AMD motherboards currently offer AEMP (no numeral), but as the memory headroom is not as high as it is on our ASUS Intel motherboards, it utilizes a more simplified tuning method. Although it does not process as many variables, the tuning method still takes into account many of the same key specs it uses in AEMP II and III, such as the DIMMs’ profiles, CPU, and motherboard memory headroom.
Q. What is the difference between AEMP II and AEMP III?
A. Only one thing: ASUS AEMP II is designed for use with DDR5 U-DIMMs with a controllable PMIC, while ASUS AEMP III is designed for use with DDR5 CU-DIMMs with a controllable PMIC.
Q. What is the difference between U-DIMM and CU-DIMM memory?
A. CU-DIMMs use a clock driver (CKD) to stabilize memory rated for higher speeds, starting around ~6500 MT/s. Otherwise, there is no difference between AEMP II and AEMP III.
You cannot POST when mixing U-DIMM and CU-DIMM memory, so you will need to check the specs on your memory. If you’re not sure which type you have, you can check the ASUS SPD Information in your UEFI BIOS to confirm your memory specs.
Q. What is the difference between single-and dual-rank memory?
A. The short answer is that memory rank refers to the organization of memory on a module, which impacts how the motherboard utilizes the DIMM. With regards to compatibility with AEMP and DIMM Fit, these technologies work with both single- and dual-rank memory. However, you cannot POST when mixing single- and dual-rank DIMMs, so please keep that in mind.
To determine if your memory is single- or dual-rank, you can install one DIMM at a time and use the ASUS SPD Information tool to check. high capacity DIMMs (32GB and higher) are more likely to be dual-rank, but you can’t just rely on physical characteristics alone.
Q. What do you mean by “motherboard memory overhead”?
A. Motherboards matter when it comes to overclocking headroom in general, and this also holds true when it comes to overclocking memory. A motherboard like the ROG Maximus Z890 Apex has the highest memory overhead of any of our motherboards, thanks to its 1DPC and proprietary tracing layout. Similarly, motherboards like our ROG Maximus Z890 Extreme and ROG Maximus Z890 Hero use our newer NitroPath DRAM Technology, which significantly improves memory overhead on 2DPC motherboards. This overhead also extends when using features like AEMP.
When memory is tuned through AEMP or DIMM Fit technologies, we incorporate our own knowledge of how each of our motherboards perform with different memory kits and profiles to extend the performance envelope of your memory. This tuning is hyper-specific and extends through our ROG, TUF Gaming, and Prime motherboards (where supported).
This is why your choice of a motherboard still matters when you build a system.
Q. Does AEMP work with only one DIMM?
A. Yes. Even selecting the more budget-friendly JEDEC industry standard modules won’t erase all the pain from elevated RAM prices. One alternative is to start with one 32GGB or 64GB JEDEC industry standard memory module and add more later.
Q. If using only one DIMM, how would that affect performance compared to using two DIMMs?
A. On modern motherboards, while a dual-channel configuration is still optimal, the latest CPUs and modern DDR5 platforms provide a narrower real-world performance gap in some scenarios when using a single DIMM than you might expect.
Without going down an exhaustive list, if you only have one DIMM, you have options. If you primarily play FPS games, a single DIMM will perform at a higher level than you might think, compared to a dual-channel configuration. On the other hand, if you play memory-intensive games, such as Civilization, you’ll likely see a larger performance delta between single-DIMM and dual-DIMM configurations.
Even still, AEMP does offer advantages for single-DIMM setups. When AEMP II/III tunes a memory DIMM, part of its consideration is the profiles of all memory modules installed. With every additional DIMM installed in a motherboard, its memory headroom goes down; if anything, we tend to only think of this when comparing 2 vs. 4 DIMMs or 1DPC vs. 2DPC scenarios. With a single DIMM, however, AEMP only has to tune a single stick, which can result in higher margins for performance and stability.
This may be a relevant consideration if you’re mixing two DIMMs with very different specs, or perhaps you have a second DIMM that you suspect might be failing. In these situations, it may be preferable to rely on a single higher-performing DIMM.
Q. Where can I learn more about ASUS Intel Z890 and B860 motherboards?
A. We have a great landing page with overviews, detailed information, feature introductions, and a helpful selection tool to make it easy to select your next ASUS motherboard here.
For those that want a spec-by-spec comparison, look for the “Full Specs” button around halfway down the page. You can download a PDF that lists all the boards by spec and feature so that you can compare them yourself.