DDR5 memory has come a long way from its rocky start. When DDR5 launched alongside Intel's 12th Gen CPUs, it was essentially unavailable worldwide and if you could buy it, it was exorbitantly priced. That’s changed now. The worst of the supply issues are behind us and DDR5 kits are in plentiful supply, even the highest performing ones. Prices are still too high compared to DDR4 and price parity is a long way off, but DDR5 is more affordable than it was at the start of the year.
High-performing kits still command a premium though and the G.Skill Trident Z5 RGB DDR5-6400 2x 16GB kit is certainly a speedy offering. It’s not the first 6400MHz kit on the market, but we believe it’s the first to come with a CAS latency of just 32, and one of very few kits at any speed to come with a CL that low.
Straight up, this G.Skill RAM is the highest spec DDR5 memory kit on the market right now. If high-speed memory is on your shopping list, this is a kit you’ll want to look out for, though be prepared to empty your wallet as it costs $569 (£555, AU$1,079).
One of the weaknesses of DDR5 is its relatively high latency. It’s one of the reasons that a good set of Samsung-based DDR4-3600 with tight timings is still a perfectly viable gaming option. The G.Skill Trident Z5 DDR5-6400 kit with its 32-39-39-102 timings goes a long way to minimizing this deficit. Latency is just one performance measure though. There’s also all of that raw bandwidth that you get from a kit at this speed.
The kit comes in a 2x 16GB capacity with XMP 3.0 support and a 1.40V operating voltage. It uses SK Hynix ICs which are known to work well at high speed with the majority of motherboards, particularly once you’ve updated the BIOS. Even so, you’ll want to check the QVL list of your motherboard to make sure the kit is supported. If it's not listed, look for other DDR5-6400 kits. If they’re supported, you should be good to go.
Model Name: G.Skill F5-6400J3239G16GX2-TZ5RK
Memory Type: Unbuffered DDR5
Capacity: 32GB (2x 16GB)
Rated Speed: 6400MHz
Rated Latency: 32-39-39-102
Tested Voltage: 1.40v
Warranty: Limited Lifetime
XMP: Intel XMP 3.0 Ready
Price: $569 | £555 | AU$1,079
We previously reviewed G.Skill’s DDR5-6000 C36 kit (opens in new tab) which came with a silver heatspreader. The 6400 C32 kit we have here is black, and we think it looks even better. Black is easier to blend into more builds. Of course, it supports RGB and it looks great. Some kits can be overly bright or feature uncovered LEDs but the G.Skill’s more opaque covering and diffused light look really classy.
The RGB lighting can be controlled by G.Skill’s Trident Z Lighting Control app. It’s a simple and lightweight piece of software, weighing in at just 6MB. Our quick play with this app didn’t present any issues. However, if you already have a motherboard RGB control app, G.Skill says the kit should integrate with Asus, Gigabyte, MSI, and Asrock RGB control software.
We know the kit is fast on paper, it looks good, and it's widely available, but how does it perform? This brings us to one of the most enduring PC builder questions. Is it worth spending money on a very fast memory kit? The answer isn’t a simple yes or no. It depends on the applications you run and the system you're pairing it with. Sometimes it’s well worth it, while at other times a fast kit can fall within a margin of error range of a generic DDR5-4800 kit.
CPU: Intel Core i9 12900K
Motherboard: Asus ROG Maximus Z690 Apex (DDR5)
GPU: Zotac RTX 3080 Ti Amp Extreme Holo
SSD: Seagate FireCuda 530 2TB
PSU: Corsair AX1000
Chassis: Thermaltake Core P8
Cooler: Cooler Master PL360 Flux
OS: Windows 11 Build 22800.282
File compression and video encoding are two tests that show decent gains. The G.Skill kit is the fastest of all tested kits, though as it's the fastest on-paper kit, that’s not a surprise. Even less of a surprise are the stellar synthetic AIDA64 results, which show the G.Skill kit leading the way. The latency result is fantastic too.
Games tend to prefer low latency, though it varies from game to game. Civilization VI shows small gains. Metro Exodus Enhanced also shows small gains, but what's interesting about this test is that it’s GPU limited. The benefits are more apparent in CPU-limited scenarios, such as you might find when you’re looking for high frame rates with a high refresh rate screen.
To sum up, it remains the case that buying a very fast DDR5 only makes sense if you’ve got a system to match. If you're lucky enough to have a 12900K and RTX 3080 Ti in your system, then you owe it to your system to match it with a fast memory kit to get the most out of it. For just about everyone else, a kit in the 5200MHz to 6000MHz range will deliver perfectly acceptable performance in real-world scenarios.
Now that Z690 boards have been on the market for a few months, it’s clear that BIOSes have come a long way. Our Asus Maximus Z690 Apex has really improved and overclocking is a lot better than it was in the early days. SK Hynix kits are known to overclock well but we think we’re at the limits of our CPU.
We’re able to hit DDR5-6667 without adjusting the RAM voltage at all, but did have to bump up IMC voltages to levels we wouldn’t be comfortable with 24/7. If you don't mind pushing it and have a good IMC, 7,000MHz isn't out of the question. There’s no doubt it’s a kit that overclockers have been using to push out those memory world records (opens in new tab).
G.Skill memory rarely disappoints and its latest Trident Z5 DDR5-6400 CL32 kit is as good as you’ll find at this point in time. But should you buy it? Honestly? No, unless you have a very high-end system. If you’re on a budget, you’ll get more value by buying a cheaper kit and diverting the money towards a faster CPU or GPU. That will deliver a tangible performance benefit.
The G.Skill DDR5-6400 C32 kit is the fastest kit I’ve ever reviewed. There's no question that it’s very expensive and impossible to recommend to a mainstream buyer, but if you want the best kit you can get, then you’ll get a lot of satisfaction out of it. It’s one of those halo products that we want to own, even if we don’t really need it.