So I fell down the rabbit hole today of reading about dual vs single rank DDR4, as I am about to build a new pc.
Apparently Crucial is shipping DDR4 16GB sticks now that could either have dual or single rank memory, and its not listed online nor on the box. You pretty much will have to read the sticker on the ram, visually check the ram to see if it has memory on both sides, or use CPU-Z and look under the SPD tab.
I am betting they won’t be the first company to do this.
Write up here from back in January:
Other reading I did today regarding RAM:
Reviews on Newegg and Amazon are popping up now saying they are getting single rank ddr4 kits in what use to be dual rank ddr4 kits.
Pretty sure I saw a Linus video on this recently. He said they were getting different memory with the same model number with all kinds of specs and explained that it was probably a chip supply issue since the manufacturers bought chips when they could with different specs based on availability and price. He called out several individual manufacturers I’m pretty sure. He actually bought ram back from his viewers so he could get a good supply of different ones.
This isn’t that video but it’s related and I can’t find the original:
Edit: Looks like I was thinking of Linus’s different SSD yet same model video from the other thread.
Yeah, I recall @HRose bringing this up here. I’ll be tracking this thread now as well! My hardware is getting old and I want to upgrade as soon as prices get back to some sort of normality. This sounds like something to be wary of.
Don’t stress out about it too much, the real world difference will be minimal. Also, you get the same advantage by using 4 modules of single rank. If you wanna go for 32GB RAM for example, 2x16 DR should perform basically identical to 4x8 SR. So if you end up getting single rank modules, you could always consider getting two more of them for that ideal rank situation in your build. But I honestly wouldn’t bother about it.
You can’t spot dual rank by looking if the module is packed double sided. Only reading the stats when in use will give you certainty. Not even the product number has to be different. It can change over the production cycle.
When it comes to clocks and timings 3600Mhz CL16 or 3200MHz CL14 should have the best price-performance ratio for a Ryzen build currently. Don’t underestimate the importance of the timings, you want them to be tight. People tend to focus on the clock speed only.
The Crucial Ballistix you found will be a great pick, no matter if they end up being dual or single rank.
I have no idea where the 1-5-10% came from, because I haven’t watched all the videos or read all the links upthread, but keep in mind that rigorous testing of a specific component or thing often leads to very accurate and simultaneously misleading numbers. Saying component X is 5% faster than other vendors competing product Y doesn’t mean an actual user will notice a 5% faster computer. It means they’ll notice that extra speed when, and only when, a workload is put on the computer that bottlenecks on that component.
It really doesn’t much matter unless you’re CPU bound, with a fast GPU running at low resolution-- and in that scenario you’ll get very high framerates anyway. If you’re buying new memory definitely get dual rank. Otherwise don’t worry about it.
Totally overblown issue. As mentioned in this thread the 5% performance penalty only applies in case there is no other bottleneck. Over 95% of the time there will be other bottlenecks first.
I don’t question which is preferable, but if it is reasonable to spend a lot of time and worry about which you would get, when it is more or less random. I wouldn’t get worse spec or more expensive RAM just because there would be a certainty of it being dual rank. Just not worth it.
And yes, 4x single rank would behave like 2x dual rank. It’s even the case that dual rank modules can be harder to OC than single rank modules, if you want to go that route eventually. But I wouldn’t worry about that difference either. Just to show that there can even be an argument for single over dual rank in some cases.
The most important thing is that you insert your two modules into the correct slots, so dual channel is active. And that you activate the XMP profile in your BIOS. It’s an automatic OC, without you won’t get the advertised clocks and timings and really lose significant performance. This is because everything over 1600MHz (3200 dual channel) is outside the DDR4 specs and considered OC, but one that can be done completely worry free and without tinkering via XMP.
