The launch of AMD's AM5 platform was a confusing one for the press, who had to review chips and motherboards on day one. We were among them and found a few issues too, but the most confusing change was the lengthy time to train memory for DDR5 RAM. This could take a minute or so, sometimes more, which would confuse everyone since nothing would be displayed on-screen other than an LED or system BIOS code for memory. Although the initial boot time takes a while, subsequent boots are notably faster, but there's a quick UEFI change to address this issue altogether.

What is AM5 motherboard memory training?

This is vital for modern AMD processors

Random access memory (RAM) is what your PC uses to store data from programs and everything else running on the OS. The initial boot of a PC with a modern motherboard will take longer than usual because of memory training. This essentially sees the motherboard run through a checklist to ensure the installed modules will work correctly with your CPU, fine-tuning memory timings and voltages for maximum stability. This all sounds good on paper, but it can prove annoying once you've already configured the UEFI BIOS accordingly, and AM5 motherboards seem to take much longer.

Because of how AMD Ryzen CPUs are designed and built, the Infinity Fabric Clock (or FLCK) is an important part of the puzzle, and it needs to be fully synchronized to get the most out of your AMD-powered system. This is also achieved through memory training, avoiding a decoupling of FCLK and RAM due to an unsynchronized configuration, and resulting in increased latency. So, memory training is important, and while there's no way to disable it (I wouldn't recommend you do if it were possible), there is a way to get your motherboard to remember its saved training data.

With each subsequent boot, the PC will load this data instead of performing the same lengthy process. What's interesting is that this feature may not be enabled by default on your motherboard. It wasn't on mine, which resulted in longer boots each time the PC fired up. This wasn't an issue when making a hot beverage in the morning or grabbing a quick shower while the system booted, but if I wanted to sit down and start using my PC from the get-go, I had to endure a wait of a few minutes.

Change this one setting to improve boot times

I can't believe I failed to enable this sooner

The setting I changed on the ASRock B650 Aorus Elite AX Ice was enabling "Memory Context Restore" (MCR) and rebooting. That's all there was to it. This B650 foundation is great for even the most capable AMD Ryzen 9000 series CPU, and yet this setting was disabled, making the system take longer to boot each time the PC was turned on. Instead of a minute or so between turning on the system to being greeted by the OS login screen, I managed to bring this time down to just 15 seconds.

I would say, "I can't believe this isn't enabled by default," but I can understand why. Making this change can cause issues with memory, especially when swapping kits in and out. There are even some modules where manufacturers specifically state this setting should be disabled, so it's worth checking with the specifications and guidance for your system memory before making this change. There are some other extreme cases, too, such as MSI recommending that "DRAM Power Down" be disabled if MCR is enabled.

Then there's the case of something going wrong during this training process, and it being stored. With MCR enabled, the system will attempt to load this bad configuration, and your PC will likely fail to boot until CMOS is cleared. This shouldn't be an issue if you're using a single kit of RAM and don't plan on making any hardware changes for years. Simply run the training process, enable MCR in your BIOS, and call it a day. Should you encounter any failed boot attempts down the line, clear your CMOS and allow the training to commence again.

AMD has improved things with BIOS updates

But this is another fix if you're struggling

Motherboards running early AM5 BIOS software will take an age to train the RAM. Some will perform it faster than others, but there's a good chance your PC will take several minutes to boot after completing the process. Updating the BIOS version will help make it all complete faster, but you could still encounter times when your PC may take longer to boot than desired. That's where this quick (and slightly dirty) "fix" comes into play. Although there are some notable caveats with using MCR, so long as you're careful and remember it's enabled, you shouldn't have any trouble.'

I've been running my primary system with MCR enabled for months without a single RAM-related issue. There are times when the PC seems to need retraining, but this only takes a minute or so with the latest BIOS release from ASRock.