How does one determine whether a module is dual- or single-rank? Specs may tell you, but you can’t count on that. If not, physical examination is another way. A look under the edge of a module’s heat spreaders would reveal how many ICs are used. Since the ICs on most performance-oriented memory modules have an 8-bit interface, eight of those make up a 64-bit rank. (Some low-end memory uses four 16-bit ICs per rank. These “chips” tend to be rectangular.) Beyond that is overkill for most folks. Programs that run optimally with 64GB or more are generally designed for experienced or professional users who already know how much they need—or at least, who know that they need all they can get.

Hier erhält man natürlich für den Preis auch keinen ausgefallenen Kühlkörper oder sogar RGB-Beleuchtung, sondern ganz klassische grüne Riegel die optisch nicht viel leisten. Moreover, most of that gain can simply be achieved by moving from one rank per channel to two, something that you might accomplish by simply adding another two matched-spec modules to a machine that has two empty slots. So bear that in mind as you shop the sales.It may be an Intel technology, but enthusiast-class AMD motherboards are also designed to support XMP. As motherboards are often programmed to slightly alter certain timings to further stabilize AMD’s different memory controllers, motherboard manufacturers have occasionally applied their own names to this setting, such as Asus and its D.O.C.P. The search ends here for some PC upgraders, as some machines simply can’t be upgraded. The above screenshots, for example, come from an old, DDR3-equipped notebook that doesn’t support modules of 8GB each and already has its two slots filled with 4GB memory modules. A key thing for starters: DDR3 is a sign of an older PC, and you can’t simply swap in DDR4 modules in their place. On both laptops and desktops, DDR3 and DDR4 memory are keyed differently from one another and are incompatible. But if you’re not getting this information from the manufacturer, there are other ways to figure it out.

Each dual inline memory module (DIMM) has two 64-bit interfaces (one on each side) connected in series. Each interface supports one rank of memory, so that a single-sided module usually has one filled rank, and a double-sided module usually has both ranks filled. (Caveat alert: Though less common, some memory has through-paths, or “vias,” that connect both sides to a single interface.) Since the two sides of a dual-rank module are connected in series, one might not expect the added rank of memory ICs (integrated circuits, i.e. “chips”) to improve performance. This is where interleaving comes into play. Interleaving allows two different operations to occur simultaneously, such as accessing data on one rank while transferring data on the other. One thing to remember is that most systems require a matched pair of modules to run dual-channel mode, or four matching modules to operate in quad-channel mode. While past platforms have occasionally allowed for mixed modes using different modules, those didn’t perform optimally. That doesn’t necessarily mean that you have to ditch an old pair of modules when a pair of empty slots are available, as we’ve had good experience adding a new matched pair to an old matched pair of the same data rate, but doing so may make XMP mode unworkable. We’ve even added 2x 8GB kits next to 2x 4GB kits without breaking dual-channel mode, creating a 24GB (12GB per-channel) configuration as 8GB-4GB-8GB-4GB, by simply leaving the board at default (non-XMP) settings. You’ll just want to make sure the matched pairs are inserted into the proper paired DIMM slots recommended by the motherboard maker. Yes, that's some in-the-weeds math. But this explains why in our lead example, DDR4-3600 CAS 20 (11ns) can underperform DDR4-3200 CAS 14 (8.75ns) in certain operations: It takes 2.25ns longer for DDR4-3600 CAS 20 to respond. Most memory buyers won’t get down to that level of granularity, but that explains why you can’t weigh just a single specification in assessing performance memory. Even though these two are completely different platforms, both support DDR4-3600 at a synchronized FCLK. AMD recommended DDR4-3200 at the time of the launch of the Ryzen 3000 Series, and buyers who can’t afford DDR4-3600 at reasonable timings (CAS 18 or lower) might wish to consider this less-expensive option. ▶ Intel Z390, H370, B360, and Z370 Chipset Motherboards (With 8th and 9th Generation CPUs) DDR3 is the sign of a geriatric PC, and spending to the max on performance-minded RAM for a platform that is fast disappearing in the rearview mirror may be false economy. Most DDR3 motherboards supported at least DDR3-1600, with later examples such as the AMD 990FX and Intel Z97 often exceeding DDR3-2133 and DDR3-2800, respectively.But that long familiarity we have with DDR4 doesn’t make memory upgrades today any less complex. How do you go about buying the best memory configuration for your PC? Whether you are building a PC new or upgrading the one you have, the answers come easily—but only once you know the right questions to ask. Remember that Threadripper X399 boards tend to have eight memory slots. Breaking from DDR4-3600 recommendations because many builders wish to fully populate these boards with eight dual rank modules (16 total ranks), stability at this setting is still common when using up to eight total ranks with the Ryzen Threadripper 2950X. Earlier processors can be fussier, though. DDR4-3200 is compatible across most Threadripper processor models and memory configurations, but AMD recommends only DDR4-2933 for second-gen Ryzen Threadrippers and DDR4-2666 for first-gen Ryzen Threadrippers. ▶ Intel X299 Chipset Motherboards (With LGA2066 Core X-Series CPUs) DDR4 was launched primarily at per-module capacities of 4GB to 16GB each, while DDR3 modules favored 1GB to 4GB capacities per module. The upper limits of these specifications were twice as high, but it took several years for 32GB DDR4 and 8GB DDR3 modules to reach the consumer market after the introduction of the memory type. Because of those delays, many older motherboards required a firmware update to support the bigger, later capacity. (As seen in the earlier “old Dell notebook” example, many platforms never got those updates.) Man bekommt hier einen guten und günstigen Marken-Arbeitsspeicher. Ich habe mich für die 16GB Version entschieden, die ich in einem SFF-Rechner mit Debian benötige. Mir war weder die Geschwindigkeit, noch die Timings wichtig. Nur günstig und von einem renommierten Hersteller sollte er sein.