AMD Ryzen 9 7900X Performance With ECC DDR5 Memory

For those curious about the performance implications of using DDR5 ECC memory with AMD Ryzen 7000 series "Zen 4" processors, I ran some benchmarks with ECC memory with the Error Correction Code functionality enabled and then disabled for evaluating the impact.

ECC memory overhead impact with hardware the past number of years has typically been quite insignificant: typically 1~3% or even no statistical significance for many workloads. With the ECC DDR5 memory support for AMD Ryzen 7000 series processors on supported motherboards, I was curious -- and something many Phoronix readers have inquired about -- and ran some benchmarks with ECC enabled and then disabled.

The biggest barrier to ECC memory use with AMD Ryzen desktop processors remains with motherboard compatibility for those officially supporting ECC DDR5 for Ryzen 7000 series use. Thankfully, as covered previously on Phoronix, there are a growing number of options with AMD and their partners increasingly looking at Ryzen 7000 series for budget servers. My testing the past number of weeks has been with the ASRock Rack 1U4LW-B650/2L2T 1U barebones server that has an ASRock Rack ASRockRack B650D4U-2L2T/BCM motherboard.

The ASRock Rack B650D4U-2L2T/BCM is a micro-ATX motherboard for Ryzen 7000 series that has four DDR5 DIMM slots and can handle both ECC and non-ECC UDIMMs. The memory support list includes a number of ECC and non-ECC options that are supported from Hynix, Micron / Crucial, Kingston, and Samsung.

The ASRock Rack B650D4U-2L2T/BCM retails for above $500 USD which is expensive for a B650 chipset motherboard if going by desktop standards, but alas it's a server motherboard: besides ECC memory support, this motherboard has dual 10GbE and dual 1GbE Ethernet ports, IPMI remote management, and is of server class build quality.

The bigger performance hindrance than ECC itself is the lower memory speeds found with DDR5 ECC UDIMMs typically at DDR5-4800 but a few models exist at DDR5-5200, compared to non-ECC desktop DDR5 memory commonly able to run at DDR5-6000 or higher with Zen 4 via OC / memory profiles. For this round of ECC comparison tests, the ASRock Rack B650D4U-2L2T/BCM was successfully running with Micron 2 x 32GB MTC20C2085S1EC48BA1 Crucial DDR5-4800 ECC memory modules. The MTC20C2085S1EC48BA1 modules currently retail around $126~135 USD per 32GB DIMM.

Via the ASRock Rack BIOS, the ECC memory support was enabled/disabled for looking at the impact on performance when using an AMD Ryzen 9 7900X and running a range of workloads. Thanks to AMD and ASRock Rack for providing this 1U barebones Ryzen server for making this round of testing possible.