Muskin’s P/N MRC4U440KRRP16GX2 comes with incredible CAS 19 timings at DDR4-4400. Can this much speed overcome the added controller latency of Intel’s Gear 2 mode?
One thing that became immediately clear regarding Intel’s Alder Lake architecture is that its memory controller can run at a much higher clock than that of the models it replaced: Our test showed DDR4-4000 running normally using Intel’s “Gear 1” mode (a 1:1 memory controller to DRAM ratio), whereas earlier models required a switch to Gear 2 (1:2 ratio) to continue functioning somewhere around DDR4-3733. Given that those data rates are doubled, the new memory controller is pushing past 2GHz while the previous version gave up at around 1.67 GHz.
We still haven’t seen our Core i9-12900KF’s memory controller reliably push past 2.1GHz. Getting to DDR4-4400 thus requires the memory controller to run at something less than the memory’s clock frequency, using the previously mentioned 1:2 divider of Intel “Gear 2”. But running the memory controller at half the memory frequency brings with it added latency, and overcoming that penalty requires memory manufacturers to increase data rate and/or decrease latency by a spectacular amount: Enter Mushkin’s P/N MRC4U440KRRP16GX2 DDR4-4400 C19 Kit, a part so new that it isn’t even indexed yet!
Each Redline Frostbyte MRC4U440KRRP16GX2 kit comes with two 16GB single-rank modules rated at DDR4-4400 with 19-26-26-46 timings. Our motherboard automatically selected its JEDEC-specified DDR4-2666 CAS 19 timings, but enabling XMP within our motherboard’s UEFI GUI took it straight to its rated frequency and timings, along with the extra voltage needed to stabilize it at these bleeding-edge speeds.
Like all of its other DRAM, Mushkin’s Redline Frostbyte MRC4U440KRRP16GX2 kit carries a lifetime limited warranty.
|CPU||Intel Core i9-12900KF: 16C/24T, 3.2-5.2 GHz, 30 MB L3 Cache, LGA 1700|
|CPU Cooler||Alphacool Eisblock XPX CPU, VPP655 / Eisbecher D5 150mm, NexXxoS UT60 X-Flow|
|Comparison Memory||Mushkin MRC4U360GKK16GX2 2x16GB (32GB) DDR4-3600 Kit|
|Graphics||Gigabyte GeForce RTX 2070 Gaming OC 8G: 1410-1725 MHz GPU, GDDR6|
|Power||be quiet! Dark Power Pro 10 850W: ATX12V v2.3, EPS12V, 80 PLUS Platinum|
|Hard Drive||TOSHIBA OCZ RD400 256GB NVMe 1.1b SSD|
|Sound||Integrated HD Audio|
|Graphics Driver||GeForce 496.49|
We tested the Redline DDR4-4400 kit at various voltage levels and simply could not push it to the CPU’s next memory multiplier. Rather than mess around with base clock we tried for tighter timings and eventually got the kit stable at DDR4-4400 CAS 19-22-22-44. For comparison we used Mushkin’s Redline Frostbyte DDR4-3600 P/N MRC4U360GKK16GX2 kit, and likewise found that its timings could be stably reduced from its rated 16-19-19-39 to 15-18-18-34. Unlike the DDR4-4400 kit, the DDR4-3600 kit had some room for overclocking, reaching DDR4-4266 at CAS 22.
As expected, both bandwidth and latency increase with frequency, where high latency is a bad thing. Simplified math tells us that DDR4-4400 should be quicker at CAS 19 than DDR4-3600 is at CAS 16 (16/3600×4400=19.6), so any performance lost to latency can only be attributed to the CPU’s need to run its memory controller clock at half of memory clock (Gear 2 mode) at this high data rate. With that in mind, we’ll look at a couple applications to see whether bandwidth imparts a bigger impact than latency.
Adobe Premiere Pro shows a slight favor for the improved bandwidth of DDR4-4400, and even gains a bit from our efforts to improve latency settings at that frequency. File compression with 7-Zip goes in the other direction, favoring lower latency over higher bandwidth. The fact that there’s only a 1-2% difference between DDR4-3600 CAS 16 and DDR4-4400 CAS 19 in real-world benchmarks destroys our ability to make a strong argument either way.
And so we won’t: With so little to discuss regarding performance, the only thing left to talk about is availability. While Mushkin’s DDR4-4400 P/N MRC4U440KRRP16GX2 is still not available, its MRC4U360GKKP16GX2 DDR4-3600 is at least available for direct import from some of its foreign resellers. Those of us who really want the DDR4-4400 model are required to wait.
|Because Mushkin’s DDR4-4400 C19 kit provides excellent stability and competitive timings at a high data rate, we expect this part number MRC4U440KRRP16GX2 to be a hit within the small niche of overclockers it serves.|