Overclocking

The ASRock B550 PG Riptide has some problems when it comes to overclocking the CPU. First off, the BIOS is not particularly user-friendly to navigate. Those unfamiliar with AMD naming conventions will need to refer to the manual or seek online help to proceed.

Similar to the X570S PG Ripde, I had an issue with CPU overclocking while a memory XMP profile was enabled. Specifically, it failed the Prime95 stability test with an automatic system reboot within five to thirty seconds after initiating the torture test. I found this issue after the X570 review was published, but was aware of it this time around as the B550 version shares the same BIOS and VRM design. After a bit of investigation by trying different configurations, I found out that it has nothing to do specifically with an XMP profile being enabled. It actually has to do with the memory frequency. Anything set above DDR4-2933 caused these seemly unexplainable reboots during load testing.

If the system memory is set to DDR4-2933 or below, I can achieve an all-core overclocking of 4.2 GHz at 1.4 V with a Ryzen 9 3900X. This was accomplished by setting the load-line calibration (LLC) to level 1, which is the highest for ASRock. ASUS, for instance, has the numbering set in the opposite direction. It should thus be noted that the lowest LCC value isn't the best for every manufacturer. The extra voltage was necessary owing to the immense vdroop under load. Even with an LLC of 1, the voltage still dropped to 1.34 V when stress-testing. This usually resulted in instant reboots the second I started Prime95, until 1.4 V was reached to offset this.

For this motherboard, I would personally leave the CPU alone and not overclock it at all. You will avoid system stability issues and generally enjoy higher single-core clock frequencies with AMD's built-in Precision Boost (PBO).

Memory Overclock

The ASRock B550 PG Riptide has a few issues when it comes to system memory. For starters, if you enable XMP and it fails to post, the board will not give you a warning of the failure. It will just reboot three times, the default number of attempts, before directly going to the selected boot device. Those who expect an applied overclocked failure message will assume it worked. Open CPU-Z and you will find out that the memory profile was not applied, and it is in fact running the memory at DDR4-2133.

This becomes an even bigger problem when trying to synchronize the Infinity Fabric (FCLK) with the memory frequency. If it fails, either the board will revert back to defaults and not tell you or get stuck on the board post. The support debug LEDs above the DIMM slots do not help as they are always lit red. By default, the motherboard SoC voltage is set to 1.1 V in the BIOS. This is not a problem unless you are trying to synchronize DDR4-3800 and above with the FCLK. Even some Ryzen CPUs need 1.15 V SoC for DDR4-3600.


Using a G.Skill DDR4-5066 2x 8 GB kit, I managed to find the soft limit of this board, which is DDR4-4600. I say this is only the soft limit because different CPU memory controllers (IMC) and memory kits have achieved better results. However, I am confident that this is the stopping point for most users. I could not get anything above to post with extra loose primary timings and an unusually high SoC voltage of 1.25 V. For reference, this same CPU and memory combination can achieve DDR5-5100 with less voltage and lower primary timings.

As many AMD users already know, the best memory configuration is to match the Infinity Fabric frequency with the system memory. It becomes a game of lowest primary timings at the highest-possible memory speed without breaking the synchronization. This ends up being anywhere from DDR4-3600 to DDR4-4133 depending on the CPU and motherboard. For the Ryzen 9 3900X, which is a Zen 2 CPU, this limit is DDR4-3600 (1800 MHz) for my test system.

By installing a Ryzen 7 5800X of the next generation (Zen 3), I linked it at DDR4-3800 (1900 MHz). It took 1.2 V for the SoC, which is acceptable. I would suggest sticking to a DDR4-3600 kit for this B550 Riptide. It took a lot of trial and error to get everything to post properly and pass stability tests. Just remember that manually overclocking the CPU as well will introduce more unwanted problems.