What Does the “+” in Supported DDR4 RAM Memory Types Mean?


If you are preparing to replace hardware in your computer or build one of your own, then some of the supported memory types shown for motherboards may be a bit confusing. What does the “+” that is sometimes shown for DDR4 RAM really mean? Today’s SuperUser Q&A post has the answer to a confused reader’s question.

Today’s Question & Answer session comes to us courtesy of SuperUser—a subdivision of Stack Exchange, a community-driven grouping of Q&A web sites.

Photo courtesy of Tecnomovida Caracas (Flickr).

The Question

SuperUser reader Karl Richter wants to know what the “+” in supported DDR4 RAM memory types means:

Some motherboard producers add a “+” to the specification of supported memory types (i.e. ASRock X99 Extreme 3 supports DDR4-3000+). Does DDR4-3000+ somehow differ from DDR4-3000? The Wikipedia article on DDR-SDRAM does not contain the “+” or mention anything related. I do not see the difference reflected in selection filters when browsing online stores either.

What does the “+” in supported DDR4 RAM memory types mean?

The Answer

SuperUser contributor Yass has the answer for us:

The “+” usually indicates that the motherboard supports RAM with a frequency of over 3000 MHz. The OC in brackets means that the motherboard allows the RAM to be over-clocked. The caveats being that you may need to increase the voltage and/or the timings in order to accommodate the higher frequency.

This article provides a good explanation of memory timings (i.e. 9-9-9-24):

Memory Timings/Latency Explained

Have something to add to the explanation? Sound off in the comments. Want to read more answers from other tech-savvy Stack Exchange users? Check out the full discussion thread here.

Akemi Iwaya is a devoted Mozilla Firefox user who enjoys working with multiple browsers and occasionally dabbling with Linux. She also loves reading fantasy and sci-fi stories as well as playing "old school" role-playing games. You can visit her on Twitter and .